Merge loops/datalog into architecture: tokenizer/parser, magic sets, negation, semi-naive (259/259 tests)
This commit is contained in:
157
lib/datalog/aggregates.sx
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157
lib/datalog/aggregates.sx
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;; lib/datalog/aggregates.sx — count / sum / min / max / findall.
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;;
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;; Surface form (always 3-arg after the relation name):
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;;
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;; (count Result Var GoalLit)
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;; (sum Result Var GoalLit)
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;; (min Result Var GoalLit)
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;; (max Result Var GoalLit)
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;; (findall List Var GoalLit)
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;;
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;; Parsed naturally because arg-position compounds are already allowed
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;; (Phase 4 needs them for arithmetic). At evaluation time the aggregator
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;; runs `dl-find-bindings` on `GoalLit` under the current subst, collects
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;; the distinct values of `Var`, and binds `Result`.
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;;
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;; Aggregation is non-monotonic — `count(C, X, p(X))` shrinks as p loses
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;; tuples. The stratifier (lib/datalog/strata.sx) treats every aggregate's
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;; goal relation as a negation-like edge so the inner relation is fully
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;; derived before the aggregate fires.
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;;
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;; Empty input: count → 0, sum → 0, min/max → no binding (rule fails).
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(define dl-aggregate-rels (list "count" "sum" "min" "max" "findall"))
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(define
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dl-aggregate?
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(fn
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(lit)
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(and
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(list? lit)
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(>= (len lit) 4)
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(let ((rel (dl-rel-name lit)))
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(cond
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((nil? rel) false)
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(else (dl-member-string? rel dl-aggregate-rels)))))))
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;; Apply aggregation operator to a list of (already-distinct) numeric or
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;; symbolic values. Returns the aggregated value, or :empty if min/max
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;; has no input.
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(define
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dl-do-aggregate
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(fn
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(op vals)
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(cond
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((= op "count") (len vals))
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((= op "sum") (dl-sum-vals vals 0))
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((= op "findall") vals)
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((= op "min")
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(cond
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((= (len vals) 0) :empty)
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(else (dl-min-vals vals 1 (first vals)))))
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((= op "max")
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(cond
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((= (len vals) 0) :empty)
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(else (dl-max-vals vals 1 (first vals)))))
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(else (error (str "datalog: unknown aggregate " op))))))
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(define
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dl-sum-vals
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(fn
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(vals acc)
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(cond
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((= (len vals) 0) acc)
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(else (dl-sum-vals (rest vals) (+ acc (first vals)))))))
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(define
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dl-min-vals
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(fn
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(vals i cur)
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(cond
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((>= i (len vals)) cur)
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(else
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(let ((v (nth vals i)))
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(dl-min-vals vals (+ i 1) (if (< v cur) v cur)))))))
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(define
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dl-max-vals
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(fn
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(vals i cur)
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(cond
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((>= i (len vals)) cur)
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(else
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(let ((v (nth vals i)))
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(dl-max-vals vals (+ i 1) (if (> v cur) v cur)))))))
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;; Membership check by deep equality (so 30 == 30.0 etc).
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(define
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dl-val-member?
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(fn
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(v xs)
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(cond
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((= (len xs) 0) false)
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((dl-tuple-equal? v (first xs)) true)
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(else (dl-val-member? v (rest xs))))))
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;; Evaluate an aggregate body lit under `subst`. Returns the list of
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;; extended substitutions (0 or 1 element).
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(define
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dl-eval-aggregate
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(fn
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(lit db subst)
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(let
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((op (dl-rel-name lit))
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(result-var (nth lit 1))
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(agg-var (nth lit 2))
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(goal (nth lit 3)))
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(cond
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((not (dl-var? agg-var))
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(error (str "datalog aggregate (" op
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"): second arg must be a variable, got " agg-var)))
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((not (and (list? goal) (> (len goal) 0)
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(symbol? (first goal))))
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(error (str "datalog aggregate (" op
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"): third arg must be a positive literal, got "
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goal)))
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((not (dl-member-string?
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(symbol->string agg-var)
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(dl-vars-of goal)))
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(error (str "datalog aggregate (" op
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"): aggregation variable " agg-var
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" does not appear in the goal " goal
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" — without it every match contributes the same "
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"(unbound) value and the result is meaningless")))
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(else
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(let ((vals (list)))
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(do
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(for-each
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(fn
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(s)
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(let ((v (dl-apply-subst agg-var s)))
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(when (not (dl-val-member? v vals))
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(append! vals v))))
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(dl-find-bindings (list goal) db subst))
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(let ((agg-val (dl-do-aggregate op vals)))
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(cond
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((= agg-val :empty) (list))
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(else
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(let ((s2 (dl-unify result-var agg-val subst)))
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(if (nil? s2) (list) (list s2)))))))))))))
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;; Stratification edges from aggregates: like negation, the goal's
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;; relation must be in a strictly lower stratum so that the aggregate
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;; fires only after the underlying tuples are settled.
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(define
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dl-aggregate-dep-edge
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(fn
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(lit)
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(cond
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((dl-aggregate? lit)
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(let ((goal (nth lit 3)))
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(cond
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((and (list? goal) (> (len goal) 0))
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(let ((rel (dl-rel-name goal)))
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(if (nil? rel) nil {:rel rel :neg true})))
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(else nil))))
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(else nil))))
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303
lib/datalog/api.sx
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303
lib/datalog/api.sx
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@@ -0,0 +1,303 @@
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;; lib/datalog/api.sx — SX-data embedding API.
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;;
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;; Where Phase 1's `dl-program` takes a Datalog source string,
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;; this module exposes a parser-free API that consumes SX data
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;; directly. Two rule shapes are accepted:
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;;
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;; - dict: {:head <literal> :body (<literal> ...)}
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;; - list: (<head-elements...> <- <body-literal> ...)
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;; — `<-` is an SX symbol used as the rule arrow.
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;;
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;; Examples:
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;;
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;; (dl-program-data
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;; '((parent tom bob) (parent tom liz) (parent bob ann))
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;; '((ancestor X Y <- (parent X Y))
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;; (ancestor X Z <- (parent X Y) (ancestor Y Z))))
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;;
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;; (dl-query db '(ancestor tom X)) ; same query API as before
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;;
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;; Variables follow the parser convention: SX symbols whose first
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;; character is uppercase or `_` are variables.
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(define
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dl-rule
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(fn (head body) {:head head :body body}))
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(define
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dl-rule-arrow?
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(fn
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(x)
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(and (symbol? x) (= (symbol->string x) "<-"))))
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(define
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dl-find-arrow
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(fn
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(rl i n)
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(cond
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((>= i n) nil)
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((dl-rule-arrow? (nth rl i)) i)
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(else (dl-find-arrow rl (+ i 1) n)))))
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;; Given a list of the form (head-elt ... <- body-lit ...) returns
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;; {:head (head-elt ...) :body (body-lit ...)}. If no arrow is
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;; present, the whole list is treated as the head and the body is
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;; empty (i.e. a fact written rule-style).
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(define
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dl-rule-from-list
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(fn
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(rl)
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(let ((n (len rl)))
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(let ((idx (dl-find-arrow rl 0 n)))
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(cond
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((nil? idx) {:head rl :body (list)})
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(else
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(let
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((head (slice rl 0 idx))
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(body (slice rl (+ idx 1) n)))
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{:head head :body body})))))))
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;; Coerce a rule given as either a dict or a list-with-arrow to a dict.
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(define
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dl-coerce-rule
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(fn
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(r)
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(cond
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((dict? r) r)
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((list? r) (dl-rule-from-list r))
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(else (error (str "dl-coerce-rule: expected dict or list, got " r))))))
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;; Build a db from SX data lists.
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(define
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dl-program-data
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(fn
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(facts rules)
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(let ((db (dl-make-db)))
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(do
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(for-each (fn (lit) (dl-add-fact! db lit)) facts)
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(for-each
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(fn (r) (dl-add-rule! db (dl-coerce-rule r)))
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rules)
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db))))
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;; Add a single fact at runtime, then re-saturate the db so derived
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;; tuples reflect the change. Returns the db.
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(define
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dl-assert!
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(fn
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(db lit)
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(do
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(dl-add-fact! db lit)
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(dl-saturate! db)
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db)))
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;; Remove a fact and re-saturate. Mixed relations (which have BOTH
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;; user-asserted facts AND rules) are supported via :edb-keys provenance
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;; — explicit facts are marked at dl-add-fact! time, the saturator uses
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;; dl-add-derived! which doesn't mark them, so the retract pass can
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;; safely wipe IDB-derived tuples while preserving the user's EDB.
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;;
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;; Effect:
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;; - remove tuples matching `lit` from :facts and :edb-keys
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;; - for every relation that has a rule (i.e. potentially IDB or
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;; mixed), drop the IDB-derived portion (anything not in :edb-keys)
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;; so the saturator can re-derive cleanly
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;; - re-saturate
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(define
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dl-retract!
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(fn
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(db lit)
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(let
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((rel-key (dl-rel-name lit)))
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(do
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;; Drop the matching tuple from its relation list, its facts-keys,
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;; its first-arg index, AND from :edb-keys (if present).
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(when
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(has-key? (get db :facts) rel-key)
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(let
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((existing (get (get db :facts) rel-key))
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(kept (list))
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(kept-keys {})
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(kept-index {})
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(edb-rel (cond
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((has-key? (get db :edb-keys) rel-key)
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(get (get db :edb-keys) rel-key))
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(else nil)))
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(kept-edb {}))
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(do
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(for-each
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(fn
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(t)
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(when
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(not (dl-tuple-equal? t lit))
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(do
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(append! kept t)
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(let ((tk (dl-tuple-key t)))
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(do
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(dict-set! kept-keys tk true)
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(when
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(and (not (nil? edb-rel))
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(has-key? edb-rel tk))
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(dict-set! kept-edb tk true))))
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(when
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(>= (len t) 2)
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(let ((k (dl-arg-key (nth t 1))))
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(do
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||||
(when
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||||
(not (has-key? kept-index k))
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(dict-set! kept-index k (list)))
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(append! (get kept-index k) t)))))))
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existing)
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(dict-set! (get db :facts) rel-key kept)
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(dict-set! (get db :facts-keys) rel-key kept-keys)
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(dict-set! (get db :facts-index) rel-key kept-index)
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(when
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(not (nil? edb-rel))
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(dict-set! (get db :edb-keys) rel-key kept-edb)))))
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;; For each rule-head relation, strip the IDB-derived tuples
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;; (anything not marked in :edb-keys) so the saturator can
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;; cleanly re-derive without leaving stale tuples that depended
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;; on the now-removed fact.
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(let ((rule-heads (dl-rule-head-rels db)))
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(for-each
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||||
(fn
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(k)
|
||||
(when
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||||
(has-key? (get db :facts) k)
|
||||
(let
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((existing (get (get db :facts) k))
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(kept (list))
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(kept-keys {})
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(kept-index {})
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(edb-rel (cond
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((has-key? (get db :edb-keys) k)
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(get (get db :edb-keys) k))
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(else {}))))
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(do
|
||||
(for-each
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||||
(fn
|
||||
(t)
|
||||
(let ((tk (dl-tuple-key t)))
|
||||
(when
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||||
(has-key? edb-rel tk)
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||||
(do
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||||
(append! kept t)
|
||||
(dict-set! kept-keys tk true)
|
||||
(when
|
||||
(>= (len t) 2)
|
||||
(let ((kk (dl-arg-key (nth t 1))))
|
||||
(do
|
||||
(when
|
||||
(not (has-key? kept-index kk))
|
||||
(dict-set! kept-index kk (list)))
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(append! (get kept-index kk) t))))))))
|
||||
existing)
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||||
(dict-set! (get db :facts) k kept)
|
||||
(dict-set! (get db :facts-keys) k kept-keys)
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||||
(dict-set! (get db :facts-index) k kept-index)))))
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||||
rule-heads))
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||||
(dl-saturate! db)
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||||
db))))
|
||||
|
||||
;; ── Convenience: single-call source + query ───────────────────
|
||||
;; (dl-eval source query-source) parses both, builds a db, saturates,
|
||||
;; runs the query, returns the substitution list. The query source
|
||||
;; should be `?- goal[, goal ...].` — the parser produces a clause
|
||||
;; with :query containing a list of literals which is fed straight
|
||||
;; to dl-query.
|
||||
(define
|
||||
dl-eval
|
||||
(fn
|
||||
(source query-source)
|
||||
(let
|
||||
((db (dl-program source))
|
||||
(queries (dl-parse query-source)))
|
||||
(cond
|
||||
((= (len queries) 0) (error "dl-eval: query string is empty"))
|
||||
((not (has-key? (first queries) :query))
|
||||
(error "dl-eval: second arg must be a `?- ...` query clause"))
|
||||
(else
|
||||
(dl-query db (get (first queries) :query)))))))
|
||||
|
||||
;; (dl-eval-magic source query-source) — like dl-eval but routes a
|
||||
;; single-positive-literal query through `dl-magic-query` for goal-
|
||||
;; directed evaluation. Multi-literal query bodies fall back to the
|
||||
;; standard dl-query path (magic-sets is currently only wired for
|
||||
;; single-positive goals). The caller's source is parsed afresh
|
||||
;; each call so successive invocations are independent.
|
||||
(define
|
||||
dl-eval-magic
|
||||
(fn
|
||||
(source query-source)
|
||||
(let
|
||||
((db (dl-program source))
|
||||
(queries (dl-parse query-source)))
|
||||
(cond
|
||||
((= (len queries) 0) (error "dl-eval-magic: query string is empty"))
|
||||
((not (has-key? (first queries) :query))
|
||||
(error
|
||||
"dl-eval-magic: second arg must be a `?- ...` query clause"))
|
||||
(else
|
||||
(let
|
||||
((qbody (get (first queries) :query)))
|
||||
(cond
|
||||
((and (= (len qbody) 1)
|
||||
(list? (first qbody))
|
||||
(> (len (first qbody)) 0)
|
||||
(symbol? (first (first qbody))))
|
||||
(dl-magic-query db (first qbody)))
|
||||
(else (dl-query db qbody)))))))))
|
||||
|
||||
;; List rules whose head's relation matches `rel-name`. Useful for
|
||||
;; inspection ("show me how this relation is derived") without
|
||||
;; exposing the internal `:rules` list.
|
||||
(define
|
||||
dl-rules-of
|
||||
(fn
|
||||
(db rel-name)
|
||||
(let ((out (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(rule)
|
||||
(when
|
||||
(= (dl-rel-name (get rule :head)) rel-name)
|
||||
(append! out rule)))
|
||||
(dl-rules db))
|
||||
out))))
|
||||
|
||||
(define
|
||||
dl-rule-head-rels
|
||||
(fn
|
||||
(db)
|
||||
(let ((seen (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(rule)
|
||||
(let ((h (dl-rel-name (get rule :head))))
|
||||
(when
|
||||
(and (not (nil? h)) (not (dl-member-string? h seen)))
|
||||
(append! seen h))))
|
||||
(dl-rules db))
|
||||
seen))))
|
||||
|
||||
;; Wipe every relation that has at least one rule (i.e. every IDB
|
||||
;; relation) — leaves EDB facts and rule definitions intact. Useful
|
||||
;; before a follow-up `dl-saturate!` if you want a clean restart, or
|
||||
;; for inspection of the EDB-only baseline.
|
||||
(define
|
||||
dl-clear-idb!
|
||||
(fn
|
||||
(db)
|
||||
(let ((rule-heads (dl-rule-head-rels db)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(k)
|
||||
(do
|
||||
(dict-set! (get db :facts) k (list))
|
||||
(dict-set! (get db :facts-keys) k {})
|
||||
(dict-set! (get db :facts-index) k {})))
|
||||
rule-heads)
|
||||
db))))
|
||||
406
lib/datalog/builtins.sx
Normal file
406
lib/datalog/builtins.sx
Normal file
@@ -0,0 +1,406 @@
|
||||
;; lib/datalog/builtins.sx — comparison + arithmetic body literals.
|
||||
;;
|
||||
;; Built-in predicates filter / extend candidate substitutions during
|
||||
;; rule evaluation. They are not stored facts and do not participate in
|
||||
;; the Herbrand base.
|
||||
;;
|
||||
;; (< a b) (<= a b) (> a b) (>= a b) ; numeric (or string) compare
|
||||
;; (= a b) ; unify (binds vars)
|
||||
;; (!= a b) ; ground-only inequality
|
||||
;; (is X expr) ; bind X to expr's value
|
||||
;;
|
||||
;; Arithmetic expressions are SX-list compounds:
|
||||
;; (+ a b) (- a b) (* a b) (/ a b)
|
||||
;; or numbers / variables (must be bound at evaluation time).
|
||||
|
||||
(define
|
||||
dl-comparison?
|
||||
(fn
|
||||
(lit)
|
||||
(and
|
||||
(list? lit)
|
||||
(> (len lit) 0)
|
||||
(let
|
||||
((rel (dl-rel-name lit)))
|
||||
(cond
|
||||
((nil? rel) false)
|
||||
(else (dl-member-string? rel (list "<" "<=" ">" ">=" "!="))))))))
|
||||
|
||||
(define
|
||||
dl-eq?
|
||||
(fn
|
||||
(lit)
|
||||
(and
|
||||
(list? lit)
|
||||
(> (len lit) 0)
|
||||
(let ((rel (dl-rel-name lit))) (and (not (nil? rel)) (= rel "="))))))
|
||||
|
||||
(define
|
||||
dl-is?
|
||||
(fn
|
||||
(lit)
|
||||
(and
|
||||
(list? lit)
|
||||
(> (len lit) 0)
|
||||
(let
|
||||
((rel (dl-rel-name lit)))
|
||||
(and (not (nil? rel)) (= rel "is"))))))
|
||||
|
||||
;; Evaluate an arithmetic expression under subst. Returns the numeric
|
||||
;; result, or raises if any operand is unbound or non-numeric.
|
||||
(define
|
||||
dl-eval-arith
|
||||
(fn
|
||||
(expr subst)
|
||||
(let
|
||||
((w (dl-walk expr subst)))
|
||||
(cond
|
||||
((number? w) w)
|
||||
((dl-var? w)
|
||||
(error (str "datalog arith: unbound variable " (symbol->string w))))
|
||||
((list? w)
|
||||
(let
|
||||
((rel (dl-rel-name w)) (args (rest w)))
|
||||
(cond
|
||||
((not (= (len args) 2))
|
||||
(error (str "datalog arith: need 2 args, got " w)))
|
||||
(else
|
||||
(let
|
||||
((a (dl-eval-arith (first args) subst))
|
||||
(b (dl-eval-arith (nth args 1) subst)))
|
||||
(cond
|
||||
((= rel "+") (+ a b))
|
||||
((= rel "-") (- a b))
|
||||
((= rel "*") (* a b))
|
||||
((= rel "/")
|
||||
(cond
|
||||
((= b 0)
|
||||
(error
|
||||
(str "datalog arith: division by zero in "
|
||||
w)))
|
||||
(else (/ a b))))
|
||||
(else (error (str "datalog arith: unknown op " rel)))))))))
|
||||
(else (error (str "datalog arith: not a number — " w)))))))
|
||||
|
||||
;; Comparable types — both operands must be the same primitive type
|
||||
;; (both numbers, both strings). `!=` is the exception: it's defined
|
||||
;; for any pair (returns true iff not equal) since dl-tuple-equal?
|
||||
;; handles type-mixed comparisons.
|
||||
(define
|
||||
dl-compare-typeok?
|
||||
(fn
|
||||
(rel a b)
|
||||
(cond
|
||||
((= rel "!=") true)
|
||||
((and (number? a) (number? b)) true)
|
||||
((and (string? a) (string? b)) true)
|
||||
(else false))))
|
||||
|
||||
(define
|
||||
dl-eval-compare
|
||||
(fn
|
||||
(lit subst)
|
||||
(let
|
||||
((rel (dl-rel-name lit))
|
||||
(a (dl-walk (nth lit 1) subst))
|
||||
(b (dl-walk (nth lit 2) subst)))
|
||||
(cond
|
||||
((or (dl-var? a) (dl-var? b))
|
||||
(error
|
||||
(str
|
||||
"datalog: comparison "
|
||||
rel
|
||||
" has unbound argument; "
|
||||
"ensure prior body literal binds the variable")))
|
||||
((not (dl-compare-typeok? rel a b))
|
||||
(error
|
||||
(str "datalog: comparison " rel " requires same-type "
|
||||
"operands (both numbers or both strings), got "
|
||||
a " and " b)))
|
||||
(else
|
||||
(let
|
||||
((ok (cond ((= rel "<") (< a b)) ((= rel "<=") (<= a b)) ((= rel ">") (> a b)) ((= rel ">=") (>= a b)) ((= rel "!=") (not (dl-tuple-equal? a b))) (else (error (str "datalog: unknown compare " rel))))))
|
||||
(if ok subst nil)))))))
|
||||
|
||||
(define
|
||||
dl-eval-eq
|
||||
(fn
|
||||
(lit subst)
|
||||
(dl-unify (nth lit 1) (nth lit 2) subst)))
|
||||
|
||||
(define
|
||||
dl-eval-is
|
||||
(fn
|
||||
(lit subst)
|
||||
(let
|
||||
((target (nth lit 1)) (expr (nth lit 2)))
|
||||
(let
|
||||
((value (dl-eval-arith expr subst)))
|
||||
(dl-unify target value subst)))))
|
||||
|
||||
(define
|
||||
dl-eval-builtin
|
||||
(fn
|
||||
(lit subst)
|
||||
(cond
|
||||
((dl-comparison? lit) (dl-eval-compare lit subst))
|
||||
((dl-eq? lit) (dl-eval-eq lit subst))
|
||||
((dl-is? lit) (dl-eval-is lit subst))
|
||||
(else (error (str "dl-eval-builtin: not a built-in: " lit))))))
|
||||
|
||||
;; ── Safety analysis ──────────────────────────────────────────────
|
||||
;;
|
||||
;; Walks body literals left-to-right tracking a "bound" set. The check
|
||||
;; understands these literal kinds:
|
||||
;;
|
||||
;; positive non-built-in → adds its vars to bound
|
||||
;; (is X expr) → vars(expr) ⊆ bound, then add X (if var)
|
||||
;; <,<=,>,>=,!= → all vars ⊆ bound (no binding)
|
||||
;; (= a b) where:
|
||||
;; both non-vars → constraint check, no binding
|
||||
;; a var, b not → bind a
|
||||
;; b var, a not → bind b
|
||||
;; both vars → at least one in bound; bind the other
|
||||
;; {:neg lit} → all vars ⊆ bound (Phase 7 enforces fully)
|
||||
;;
|
||||
;; At end, head vars (minus `_`) must be ⊆ bound.
|
||||
|
||||
(define
|
||||
dl-vars-not-in
|
||||
(fn
|
||||
(vs bound)
|
||||
(let
|
||||
((out (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(v)
|
||||
(when (not (dl-member-string? v bound)) (append! out v)))
|
||||
vs)
|
||||
out))))
|
||||
|
||||
;; Filter a list of variable-name strings to exclude anonymous-renamed
|
||||
;; vars (`_` in source → `_anon*` by dl-rename-anon-term). Used by
|
||||
;; the negation safety check, where anonymous vars are existential
|
||||
;; within the negated literal.
|
||||
(define
|
||||
dl-non-anon-vars
|
||||
(fn
|
||||
(vs)
|
||||
(let
|
||||
((out (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(v)
|
||||
(when
|
||||
(not (and (>= (len v) 5)
|
||||
(= (slice v 0 5) "_anon")))
|
||||
(append! out v)))
|
||||
vs)
|
||||
out))))
|
||||
|
||||
(define
|
||||
dl-rule-check-safety
|
||||
(fn
|
||||
(rule)
|
||||
(let
|
||||
((head (get rule :head))
|
||||
(body (get rule :body))
|
||||
(bound (list))
|
||||
(err nil))
|
||||
(do
|
||||
(define
|
||||
dl-add-bound!
|
||||
(fn
|
||||
(vs)
|
||||
(for-each
|
||||
(fn
|
||||
(v)
|
||||
(when (not (dl-member-string? v bound)) (append! bound v)))
|
||||
vs)))
|
||||
(define
|
||||
dl-process-eq!
|
||||
(fn
|
||||
(lit)
|
||||
(let
|
||||
((a (nth lit 1)) (b (nth lit 2)))
|
||||
(let
|
||||
((va (dl-var? a)) (vb (dl-var? b)))
|
||||
(cond
|
||||
((and (not va) (not vb)) nil)
|
||||
((and va (not vb))
|
||||
(dl-add-bound! (list (symbol->string a))))
|
||||
((and (not va) vb)
|
||||
(dl-add-bound! (list (symbol->string b))))
|
||||
(else
|
||||
(let
|
||||
((sa (symbol->string a)) (sb (symbol->string b)))
|
||||
(cond
|
||||
((dl-member-string? sa bound)
|
||||
(dl-add-bound! (list sb)))
|
||||
((dl-member-string? sb bound)
|
||||
(dl-add-bound! (list sa)))
|
||||
(else
|
||||
(set!
|
||||
err
|
||||
(str
|
||||
"= between two unbound variables "
|
||||
(list sa sb)
|
||||
" — at least one must be bound by an "
|
||||
"earlier positive body literal")))))))))))
|
||||
(define
|
||||
dl-process-cmp!
|
||||
(fn
|
||||
(lit)
|
||||
(let
|
||||
((needed (dl-vars-of (list (nth lit 1) (nth lit 2)))))
|
||||
(let
|
||||
((missing (dl-vars-not-in needed bound)))
|
||||
(when
|
||||
(> (len missing) 0)
|
||||
(set!
|
||||
err
|
||||
(str
|
||||
"comparison "
|
||||
(dl-rel-name lit)
|
||||
" requires bound variable(s) "
|
||||
missing
|
||||
" (must be bound by an earlier positive "
|
||||
"body literal)")))))))
|
||||
(define
|
||||
dl-process-is!
|
||||
(fn
|
||||
(lit)
|
||||
(let
|
||||
((tgt (nth lit 1)) (expr (nth lit 2)))
|
||||
(let
|
||||
((needed (dl-vars-of expr)))
|
||||
(let
|
||||
((missing (dl-vars-not-in needed bound)))
|
||||
(cond
|
||||
((> (len missing) 0)
|
||||
(set!
|
||||
err
|
||||
(str
|
||||
"is RHS uses unbound variable(s) "
|
||||
missing
|
||||
" — bind them via a prior positive body "
|
||||
"literal")))
|
||||
(else
|
||||
(when
|
||||
(dl-var? tgt)
|
||||
(dl-add-bound! (list (symbol->string tgt)))))))))))
|
||||
(define
|
||||
dl-process-neg!
|
||||
(fn
|
||||
(lit)
|
||||
(let
|
||||
((inner (get lit :neg)))
|
||||
(let
|
||||
((inner-rn
|
||||
(cond
|
||||
((and (list? inner) (> (len inner) 0))
|
||||
(dl-rel-name inner))
|
||||
(else nil)))
|
||||
;; Anonymous variables (`_` in source → `_anon*` after
|
||||
;; renaming) are existentially quantified within the
|
||||
;; negated literal — they don't need to be bound by
|
||||
;; an earlier body lit, since `not p(X, _)` is a
|
||||
;; valid idiom for "no Y exists s.t. p(X, Y)". Filter
|
||||
;; them out of the safety check.
|
||||
(needed (dl-non-anon-vars (dl-vars-of inner)))
|
||||
(missing (dl-vars-not-in needed bound)))
|
||||
(cond
|
||||
((and (not (nil? inner-rn)) (dl-reserved-rel? inner-rn))
|
||||
(set! err
|
||||
(str "negated literal uses reserved name '"
|
||||
inner-rn
|
||||
"' — nested `not(...)` / negated built-ins are "
|
||||
"not supported; introduce an intermediate "
|
||||
"relation and negate that")))
|
||||
((> (len missing) 0)
|
||||
(set! err
|
||||
(str "negation refers to unbound variable(s) "
|
||||
missing
|
||||
" — they must be bound by an earlier "
|
||||
"positive body literal"))))))))
|
||||
(define
|
||||
dl-process-agg!
|
||||
(fn
|
||||
(lit)
|
||||
(let
|
||||
((result-var (nth lit 1)))
|
||||
;; Aggregate goal vars are existentially quantified within
|
||||
;; the aggregate; nothing required from outer context. The
|
||||
;; result var becomes bound after the aggregate fires.
|
||||
(when
|
||||
(dl-var? result-var)
|
||||
(dl-add-bound! (list (symbol->string result-var)))))))
|
||||
|
||||
(define
|
||||
dl-process-lit!
|
||||
(fn
|
||||
(lit)
|
||||
(when
|
||||
(nil? err)
|
||||
(cond
|
||||
((and (dict? lit) (has-key? lit :neg))
|
||||
(dl-process-neg! lit))
|
||||
;; A bare dict that is not a recognised negation is
|
||||
;; almost certainly a typo (e.g. `{:negs ...}` instead
|
||||
;; of `{:neg ...}`). Without this guard the dict would
|
||||
;; silently fall through every clause; the head safety
|
||||
;; check would then flag the head variables as unbound
|
||||
;; even though the real bug is the malformed body lit.
|
||||
((dict? lit)
|
||||
(set! err
|
||||
(str "body literal is a dict but lacks :neg — "
|
||||
"the only dict-shaped body lit recognised is "
|
||||
"{:neg <positive-lit>} for stratified "
|
||||
"negation, got " lit)))
|
||||
((dl-aggregate? lit) (dl-process-agg! lit))
|
||||
((dl-eq? lit) (dl-process-eq! lit))
|
||||
((dl-is? lit) (dl-process-is! lit))
|
||||
((dl-comparison? lit) (dl-process-cmp! lit))
|
||||
((and (list? lit) (> (len lit) 0))
|
||||
(let ((rn (dl-rel-name lit)))
|
||||
(cond
|
||||
((and (not (nil? rn)) (dl-reserved-rel? rn))
|
||||
(set! err
|
||||
(str "body literal uses reserved name '" rn
|
||||
"' — built-ins / aggregates have their own "
|
||||
"syntax; nested `not(...)` is not supported "
|
||||
"(use stratified negation via an "
|
||||
"intermediate relation)")))
|
||||
(else (dl-add-bound! (dl-vars-of lit))))))
|
||||
(else
|
||||
;; Anything that's not a dict, not a list, or an
|
||||
;; empty list. Numbers / strings / symbols as body
|
||||
;; lits don't make sense — surface the type.
|
||||
(set! err
|
||||
(str "body literal must be a positive lit, "
|
||||
"built-in, aggregate, or {:neg ...} dict, "
|
||||
"got " lit)))))))
|
||||
(for-each dl-process-lit! body)
|
||||
(when
|
||||
(nil? err)
|
||||
(let
|
||||
((head-vars (dl-vars-of head)) (missing (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(v)
|
||||
(when
|
||||
(and (not (dl-member-string? v bound)) (not (= v "_")))
|
||||
(append! missing v)))
|
||||
head-vars)
|
||||
(when
|
||||
(> (len missing) 0)
|
||||
(set!
|
||||
err
|
||||
(str
|
||||
"head variable(s) "
|
||||
missing
|
||||
" do not appear in any positive body literal"))))))
|
||||
err))))
|
||||
32
lib/datalog/conformance.conf
Normal file
32
lib/datalog/conformance.conf
Normal file
@@ -0,0 +1,32 @@
|
||||
# Datalog conformance config — sourced by lib/guest/conformance.sh.
|
||||
|
||||
LANG_NAME=datalog
|
||||
MODE=dict
|
||||
|
||||
PRELOADS=(
|
||||
lib/datalog/tokenizer.sx
|
||||
lib/datalog/parser.sx
|
||||
lib/datalog/unify.sx
|
||||
lib/datalog/db.sx
|
||||
lib/datalog/builtins.sx
|
||||
lib/datalog/aggregates.sx
|
||||
lib/datalog/strata.sx
|
||||
lib/datalog/eval.sx
|
||||
lib/datalog/api.sx
|
||||
lib/datalog/magic.sx
|
||||
lib/datalog/demo.sx
|
||||
)
|
||||
|
||||
SUITES=(
|
||||
"tokenize:lib/datalog/tests/tokenize.sx:(dl-tokenize-tests-run!)"
|
||||
"parse:lib/datalog/tests/parse.sx:(dl-parse-tests-run!)"
|
||||
"unify:lib/datalog/tests/unify.sx:(dl-unify-tests-run!)"
|
||||
"eval:lib/datalog/tests/eval.sx:(dl-eval-tests-run!)"
|
||||
"builtins:lib/datalog/tests/builtins.sx:(dl-builtins-tests-run!)"
|
||||
"semi_naive:lib/datalog/tests/semi_naive.sx:(dl-semi-naive-tests-run!)"
|
||||
"negation:lib/datalog/tests/negation.sx:(dl-negation-tests-run!)"
|
||||
"aggregates:lib/datalog/tests/aggregates.sx:(dl-aggregates-tests-run!)"
|
||||
"api:lib/datalog/tests/api.sx:(dl-api-tests-run!)"
|
||||
"magic:lib/datalog/tests/magic.sx:(dl-magic-tests-run!)"
|
||||
"demo:lib/datalog/tests/demo.sx:(dl-demo-tests-run!)"
|
||||
)
|
||||
3
lib/datalog/conformance.sh
Executable file
3
lib/datalog/conformance.sh
Executable file
@@ -0,0 +1,3 @@
|
||||
#!/usr/bin/env bash
|
||||
# Thin wrapper — see lib/guest/conformance.sh and lib/datalog/conformance.conf.
|
||||
exec bash "$(dirname "$0")/../guest/conformance.sh" "$(dirname "$0")/conformance.conf" "$@"
|
||||
97
lib/datalog/datalog.sx
Normal file
97
lib/datalog/datalog.sx
Normal file
@@ -0,0 +1,97 @@
|
||||
;; lib/datalog/datalog.sx — public API documentation index.
|
||||
;;
|
||||
;; This file is reference-only — `load` is an epoch-protocol command,
|
||||
;; not an SX function, so it cannot reload a list of files from inside
|
||||
;; another `.sx` file. To set up a fresh sx_server session with all
|
||||
;; modules in scope, issue these loads in order:
|
||||
;;
|
||||
;; (load "lib/datalog/tokenizer.sx")
|
||||
;; (load "lib/datalog/parser.sx")
|
||||
;; (load "lib/datalog/unify.sx")
|
||||
;; (load "lib/datalog/db.sx")
|
||||
;; (load "lib/datalog/builtins.sx")
|
||||
;; (load "lib/datalog/aggregates.sx")
|
||||
;; (load "lib/datalog/strata.sx")
|
||||
;; (load "lib/datalog/eval.sx")
|
||||
;; (load "lib/datalog/api.sx")
|
||||
;; (load "lib/datalog/magic.sx")
|
||||
;; (load "lib/datalog/demo.sx")
|
||||
;;
|
||||
;; (lib/datalog/conformance.sh runs this load list automatically.)
|
||||
;;
|
||||
;; ── Public API surface ─────────────────────────────────────────────
|
||||
;;
|
||||
;; Source / data:
|
||||
;; (dl-tokenize "src") → token list
|
||||
;; (dl-parse "src") → parsed clauses
|
||||
;; (dl-program "src") → db built from a source string
|
||||
;; (dl-program-data facts rules) → db from SX data lists; rules
|
||||
;; accept either dict form or
|
||||
;; list form with `<-` arrow
|
||||
;;
|
||||
;; Construction (mutates db):
|
||||
;; (dl-make-db) empty db
|
||||
;; (dl-add-fact! db lit) rejects non-ground
|
||||
;; (dl-add-rule! db rule) rejects unsafe rules
|
||||
;; (dl-rule head body) dict-rule constructor
|
||||
;; (dl-add-clause! db clause) parser output → fact or rule
|
||||
;; (dl-load-program! db src) string source
|
||||
;; (dl-set-strategy! db strategy) :semi-naive default; :magic
|
||||
;; is informational, use
|
||||
;; dl-magic-query for actual
|
||||
;; magic-sets evaluation
|
||||
;;
|
||||
;; Mutation:
|
||||
;; (dl-assert! db lit) add + re-saturate
|
||||
;; (dl-retract! db lit) drop EDB, wipe IDB, re-saturate
|
||||
;; (dl-clear-idb! db) wipe rule-headed relations
|
||||
;;
|
||||
;; Query / inspection:
|
||||
;; (dl-saturate! db) stratified semi-naive default
|
||||
;; (dl-saturate-naive! db) reference (slow on chains)
|
||||
;; (dl-saturate-rules! db rules) per-rule-set semi-naive worker
|
||||
;; (dl-query db goal) list of substitution dicts
|
||||
;; (dl-relation db rel-name) tuple list for a relation
|
||||
;; (dl-rules db) rule list
|
||||
;; (dl-fact-count db) total ground tuples
|
||||
;; (dl-summary db) {<rel>: count} for inspection
|
||||
;;
|
||||
;; Single-call convenience:
|
||||
;; (dl-eval source query-source) parse, run, return substs
|
||||
;; (dl-eval-magic source query-source) single-goal → magic-sets
|
||||
;;
|
||||
;; Magic-sets (lib/datalog/magic.sx):
|
||||
;; (dl-adorn-goal goal) "b/f" adornment string
|
||||
;; (dl-rule-sips rule head-adn) SIPS analysis per body lit
|
||||
;; (dl-magic-rewrite rules rel adn args)
|
||||
;; rewritten rule list + seed
|
||||
;; (dl-magic-query db query-goal) end-to-end magic-sets query
|
||||
;;
|
||||
;; ── Body literal kinds ─────────────────────────────────────────────
|
||||
;;
|
||||
;; Positive (rel arg ... arg)
|
||||
;; Negation {:neg (rel arg ...)}
|
||||
;; Comparison (< X Y), (<= X Y), (> X Y), (>= X Y),
|
||||
;; (= X Y), (!= X Y)
|
||||
;; Arithmetic (is Z (+ X Y)) and (- * /)
|
||||
;; Aggregation (count R V Goal), (sum R V Goal),
|
||||
;; (min R V Goal), (max R V Goal),
|
||||
;; (findall L V Goal)
|
||||
;;
|
||||
;; ── Variable conventions ───────────────────────────────────────────
|
||||
;;
|
||||
;; Variables: SX symbols whose first char is uppercase A–Z or '_'.
|
||||
;; Anonymous '_' is renamed to a fresh _anon<N> per occurrence at
|
||||
;; rule/query load time so multiple '_' don't unify.
|
||||
;;
|
||||
;; ── Demo programs ──────────────────────────────────────────────────
|
||||
;;
|
||||
;; See lib/datalog/demo.sx — federation, content, permissions, and
|
||||
;; the canonical "cooking posts by people I follow (transitively)"
|
||||
;; example.
|
||||
;;
|
||||
;; ── Status ─────────────────────────────────────────────────────────
|
||||
;;
|
||||
;; See plans/datalog-on-sx.md — phase-by-phase progress log and
|
||||
;; roadmap. Run `bash lib/datalog/conformance.sh` to refresh
|
||||
;; `lib/datalog/scoreboard.{json,md}`.
|
||||
575
lib/datalog/db.sx
Normal file
575
lib/datalog/db.sx
Normal file
@@ -0,0 +1,575 @@
|
||||
;; lib/datalog/db.sx — Datalog database (EDB + IDB + rules) + safety hook.
|
||||
;;
|
||||
;; A db is a mutable dict:
|
||||
;; {:facts {<rel-name-string> -> (literal ...)}
|
||||
;; :rules ({:head literal :body (literal ...)} ...)}
|
||||
;;
|
||||
;; Facts are stored as full literals `(rel arg ... arg)` so they unify
|
||||
;; directly against rule body literals. Each relation's tuple list is
|
||||
;; deduplicated on insert.
|
||||
;;
|
||||
;; Phase 3 introduced safety analysis for head variables; Phase 4 (in
|
||||
;; lib/datalog/builtins.sx) swaps in the real `dl-rule-check-safety`,
|
||||
;; which is order-aware and understands built-in predicates.
|
||||
|
||||
(define
|
||||
dl-make-db
|
||||
(fn ()
|
||||
{:facts {}
|
||||
:facts-keys {}
|
||||
:facts-index {}
|
||||
:edb-keys {}
|
||||
:rules (list)
|
||||
:strategy :semi-naive}))
|
||||
|
||||
;; Record (rel-key, tuple-key) as user-asserted EDB. dl-add-fact! calls
|
||||
;; this when an explicit fact is added; the saturator (which uses
|
||||
;; dl-add-derived!) does NOT, so derived tuples never appear here.
|
||||
;; dl-retract! consults :edb-keys to know which tuples must survive
|
||||
;; the wipe-and-resaturate round-trip.
|
||||
(define
|
||||
dl-mark-edb!
|
||||
(fn
|
||||
(db rel-key tk)
|
||||
(let
|
||||
((edb (get db :edb-keys)))
|
||||
(do
|
||||
(when
|
||||
(not (has-key? edb rel-key))
|
||||
(dict-set! edb rel-key {}))
|
||||
(dict-set! (get edb rel-key) tk true)))))
|
||||
|
||||
(define
|
||||
dl-edb-fact?
|
||||
(fn
|
||||
(db rel-key tk)
|
||||
(let
|
||||
((edb (get db :edb-keys)))
|
||||
(and (has-key? edb rel-key)
|
||||
(has-key? (get edb rel-key) tk)))))
|
||||
|
||||
;; Evaluation strategy. Default :semi-naive (used by dl-saturate!).
|
||||
;; :naive selects dl-saturate-naive! (slower but easier to reason
|
||||
;; about). :magic is a marker — goal-directed magic-sets evaluation
|
||||
;; is invoked separately via `dl-magic-query`; setting :magic here
|
||||
;; is purely informational. Any other value is rejected so typos
|
||||
;; don't silently fall back to the default.
|
||||
(define
|
||||
dl-strategy-values
|
||||
(list :semi-naive :naive :magic))
|
||||
|
||||
(define
|
||||
dl-set-strategy!
|
||||
(fn
|
||||
(db strategy)
|
||||
(cond
|
||||
((not (dl-keyword-member? strategy dl-strategy-values))
|
||||
(error (str "dl-set-strategy!: unknown strategy " strategy
|
||||
" — must be one of " dl-strategy-values)))
|
||||
(else
|
||||
(do
|
||||
(dict-set! db :strategy strategy)
|
||||
db)))))
|
||||
|
||||
(define
|
||||
dl-keyword-member?
|
||||
(fn
|
||||
(k xs)
|
||||
(cond
|
||||
((= (len xs) 0) false)
|
||||
((= k (first xs)) true)
|
||||
(else (dl-keyword-member? k (rest xs))))))
|
||||
|
||||
(define
|
||||
dl-get-strategy
|
||||
(fn
|
||||
(db)
|
||||
(if (has-key? db :strategy) (get db :strategy) :semi-naive)))
|
||||
|
||||
(define
|
||||
dl-rel-name
|
||||
(fn
|
||||
(lit)
|
||||
(cond
|
||||
((and (dict? lit) (has-key? lit :neg)) (dl-rel-name (get lit :neg)))
|
||||
((and (list? lit) (> (len lit) 0) (symbol? (first lit)))
|
||||
(symbol->string (first lit)))
|
||||
(else nil))))
|
||||
|
||||
(define dl-builtin-rels (list "<" "<=" ">" ">=" "=" "!=" "is"))
|
||||
|
||||
(define
|
||||
dl-member-string?
|
||||
(fn
|
||||
(s xs)
|
||||
(cond
|
||||
((= (len xs) 0) false)
|
||||
((= (first xs) s) true)
|
||||
(else (dl-member-string? s (rest xs))))))
|
||||
|
||||
(define
|
||||
dl-builtin?
|
||||
(fn
|
||||
(lit)
|
||||
(and
|
||||
(list? lit)
|
||||
(> (len lit) 0)
|
||||
(let
|
||||
((rel (dl-rel-name lit)))
|
||||
(cond
|
||||
((nil? rel) false)
|
||||
(else (dl-member-string? rel dl-builtin-rels)))))))
|
||||
|
||||
(define
|
||||
dl-positive-lit?
|
||||
(fn
|
||||
(lit)
|
||||
(cond
|
||||
((and (dict? lit) (has-key? lit :neg)) false)
|
||||
((dl-builtin? lit) false)
|
||||
((and (list? lit) (> (len lit) 0)) true)
|
||||
(else false))))
|
||||
|
||||
(define
|
||||
dl-tuple-equal?
|
||||
(fn
|
||||
(a b)
|
||||
(cond
|
||||
((and (list? a) (list? b))
|
||||
(and (= (len a) (len b)) (dl-tuple-equal-list? a b 0)))
|
||||
((and (number? a) (number? b)) (= a b))
|
||||
(else (equal? a b)))))
|
||||
|
||||
(define
|
||||
dl-tuple-equal-list?
|
||||
(fn
|
||||
(a b i)
|
||||
(cond
|
||||
((>= i (len a)) true)
|
||||
((not (dl-tuple-equal? (nth a i) (nth b i))) false)
|
||||
(else (dl-tuple-equal-list? a b (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-tuple-member?
|
||||
(fn
|
||||
(lit lits)
|
||||
(dl-tuple-member-aux? lit lits 0 (len lits))))
|
||||
|
||||
(define
|
||||
dl-tuple-member-aux?
|
||||
(fn
|
||||
(lit lits i n)
|
||||
(cond
|
||||
((>= i n) false)
|
||||
((dl-tuple-equal? lit (nth lits i)) true)
|
||||
(else (dl-tuple-member-aux? lit lits (+ i 1) n)))))
|
||||
|
||||
(define
|
||||
dl-ensure-rel!
|
||||
(fn
|
||||
(db rel-key)
|
||||
(let
|
||||
((facts (get db :facts))
|
||||
(fk (get db :facts-keys))
|
||||
(fi (get db :facts-index)))
|
||||
(do
|
||||
(when
|
||||
(not (has-key? facts rel-key))
|
||||
(dict-set! facts rel-key (list)))
|
||||
(when
|
||||
(not (has-key? fk rel-key))
|
||||
(dict-set! fk rel-key {}))
|
||||
(when
|
||||
(not (has-key? fi rel-key))
|
||||
(dict-set! fi rel-key {}))
|
||||
(get facts rel-key)))))
|
||||
|
||||
;; First-arg index helpers. Tuples are keyed by their first-after-rel
|
||||
;; arg's `(str ...)`; when that arg is a constant, dl-match-positive
|
||||
;; uses the index instead of scanning the full relation.
|
||||
(define
|
||||
dl-arg-key
|
||||
(fn
|
||||
(v)
|
||||
(str v)))
|
||||
|
||||
(define
|
||||
dl-index-add!
|
||||
(fn
|
||||
(db rel-key lit)
|
||||
(let
|
||||
((idx (get db :facts-index))
|
||||
(n (len lit)))
|
||||
(when
|
||||
(and (>= n 2) (has-key? idx rel-key))
|
||||
(let
|
||||
((rel-idx (get idx rel-key))
|
||||
(k (dl-arg-key (nth lit 1))))
|
||||
(do
|
||||
(when
|
||||
(not (has-key? rel-idx k))
|
||||
(dict-set! rel-idx k (list)))
|
||||
(append! (get rel-idx k) lit)))))))
|
||||
|
||||
(define
|
||||
dl-index-lookup
|
||||
(fn
|
||||
(db rel-key arg-val)
|
||||
(let
|
||||
((idx (get db :facts-index)))
|
||||
(cond
|
||||
((not (has-key? idx rel-key)) (list))
|
||||
(else
|
||||
(let ((rel-idx (get idx rel-key))
|
||||
(k (dl-arg-key arg-val)))
|
||||
(if (has-key? rel-idx k) (get rel-idx k) (list))))))))
|
||||
|
||||
(define dl-tuple-key (fn (lit) (str lit)))
|
||||
|
||||
(define
|
||||
dl-rel-tuples
|
||||
(fn
|
||||
(db rel-key)
|
||||
(let
|
||||
((facts (get db :facts)))
|
||||
(if (has-key? facts rel-key) (get facts rel-key) (list)))))
|
||||
|
||||
;; Reserved relation names: built-in / aggregate / negation / arrow.
|
||||
;; Rules and facts may not have these as their head's relation, since
|
||||
;; the saturator treats them specially or they are not relation names
|
||||
;; at all.
|
||||
(define
|
||||
dl-reserved-rel-names
|
||||
(list "not" "count" "sum" "min" "max" "findall" "is"
|
||||
"<" "<=" ">" ">=" "=" "!=" "+" "-" "*" "/" ":-" "?-"))
|
||||
|
||||
(define
|
||||
dl-reserved-rel?
|
||||
(fn
|
||||
(name) (dl-member-string? name dl-reserved-rel-names)))
|
||||
|
||||
;; Internal: append a derived tuple to :facts without the public
|
||||
;; validation pass and without marking :edb-keys. Used by the saturator
|
||||
;; (eval.sx) and magic-sets (magic.sx). Returns true if the tuple was
|
||||
;; new, false if already present.
|
||||
(define
|
||||
dl-add-derived!
|
||||
(fn
|
||||
(db lit)
|
||||
(let
|
||||
((rel-key (dl-rel-name lit)))
|
||||
(let
|
||||
((tuples (dl-ensure-rel! db rel-key))
|
||||
(key-dict (get (get db :facts-keys) rel-key))
|
||||
(tk (dl-tuple-key lit)))
|
||||
(cond
|
||||
((has-key? key-dict tk) false)
|
||||
(else
|
||||
(do
|
||||
(dict-set! key-dict tk true)
|
||||
(append! tuples lit)
|
||||
(dl-index-add! db rel-key lit)
|
||||
true)))))))
|
||||
|
||||
;; A simple term — number, string, or symbol — i.e. anything legal
|
||||
;; as an EDB fact arg. Compound (list) args belong only in body
|
||||
;; literals where they encode arithmetic / aggregate sub-goals.
|
||||
(define
|
||||
dl-simple-term?
|
||||
(fn
|
||||
(term)
|
||||
(or (number? term) (string? term) (symbol? term))))
|
||||
|
||||
(define
|
||||
dl-args-simple?
|
||||
(fn
|
||||
(lit i n)
|
||||
(cond
|
||||
((>= i n) true)
|
||||
((not (dl-simple-term? (nth lit i))) false)
|
||||
(else (dl-args-simple? lit (+ i 1) n)))))
|
||||
|
||||
(define
|
||||
dl-add-fact!
|
||||
(fn
|
||||
(db lit)
|
||||
(cond
|
||||
((not (and (list? lit) (> (len lit) 0)))
|
||||
(error (str "dl-add-fact!: expected literal list, got " lit)))
|
||||
((dl-reserved-rel? (dl-rel-name lit))
|
||||
(error (str "dl-add-fact!: '" (dl-rel-name lit)
|
||||
"' is a reserved name (built-in / aggregate / negation)")))
|
||||
((not (dl-args-simple? lit 1 (len lit)))
|
||||
(error (str "dl-add-fact!: fact args must be numbers, strings, "
|
||||
"or symbols — compound args (e.g. arithmetic "
|
||||
"expressions) are body-only and aren't evaluated "
|
||||
"in fact position. got " lit)))
|
||||
((not (dl-ground? lit (dl-empty-subst)))
|
||||
(error (str "dl-add-fact!: expected ground literal, got " lit)))
|
||||
(else
|
||||
(let
|
||||
((rel-key (dl-rel-name lit)) (tk (dl-tuple-key lit)))
|
||||
(do
|
||||
;; Always mark EDB origin — even if the tuple key was already
|
||||
;; present (e.g. previously derived), so an explicit assert
|
||||
;; promotes it to EDB and protects it from the IDB wipe.
|
||||
(dl-mark-edb! db rel-key tk)
|
||||
(dl-add-derived! db lit)))))))
|
||||
|
||||
;; The full safety check lives in builtins.sx (it has to know which
|
||||
;; predicates are built-ins). dl-add-rule! calls it via forward
|
||||
;; reference; load builtins.sx alongside db.sx in any setup that
|
||||
;; adds rules. The fallback below is used if builtins.sx isn't loaded.
|
||||
(define
|
||||
dl-rule-check-safety
|
||||
(fn
|
||||
(rule)
|
||||
(let
|
||||
((head-vars (dl-vars-of (get rule :head))) (body-vars (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(lit)
|
||||
(when
|
||||
(and
|
||||
(list? lit)
|
||||
(> (len lit) 0)
|
||||
(not (and (dict? lit) (has-key? lit :neg))))
|
||||
(for-each
|
||||
(fn
|
||||
(v)
|
||||
(when
|
||||
(not (dl-member-string? v body-vars))
|
||||
(append! body-vars v)))
|
||||
(dl-vars-of lit))))
|
||||
(get rule :body))
|
||||
(let
|
||||
((missing (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(v)
|
||||
(when
|
||||
(and
|
||||
(not (dl-member-string? v body-vars))
|
||||
(not (= v "_")))
|
||||
(append! missing v)))
|
||||
head-vars)
|
||||
(cond
|
||||
((> (len missing) 0)
|
||||
(str
|
||||
"head variable(s) "
|
||||
missing
|
||||
" do not appear in any body literal"))
|
||||
(else nil))))))))
|
||||
|
||||
(define
|
||||
dl-rename-anon-term
|
||||
(fn
|
||||
(term next-name)
|
||||
(cond
|
||||
((and (symbol? term) (= (symbol->string term) "_"))
|
||||
(next-name))
|
||||
((list? term)
|
||||
(map (fn (x) (dl-rename-anon-term x next-name)) term))
|
||||
(else term))))
|
||||
|
||||
(define
|
||||
dl-rename-anon-lit
|
||||
(fn
|
||||
(lit next-name)
|
||||
(cond
|
||||
((and (dict? lit) (has-key? lit :neg))
|
||||
{:neg (dl-rename-anon-term (get lit :neg) next-name)})
|
||||
((list? lit) (dl-rename-anon-term lit next-name))
|
||||
(else lit))))
|
||||
|
||||
(define
|
||||
dl-make-anon-renamer
|
||||
(fn
|
||||
(start)
|
||||
(let ((counter start))
|
||||
(fn () (do (set! counter (+ counter 1))
|
||||
(string->symbol (str "_anon" counter)))))))
|
||||
|
||||
;; Scan a rule for variables already named `_anon<N>` (which would
|
||||
;; otherwise collide with the renamer's output). Returns the max N
|
||||
;; seen, or 0 if none. The renamer then starts at that max + 1, so
|
||||
;; freshly-introduced anonymous names can't shadow a user-written
|
||||
;; `_anon<N>` symbol.
|
||||
(define
|
||||
dl-max-anon-num
|
||||
(fn
|
||||
(term acc)
|
||||
(cond
|
||||
((symbol? term)
|
||||
(let ((s (symbol->string term)))
|
||||
(cond
|
||||
((and (>= (len s) 6) (= (slice s 0 5) "_anon"))
|
||||
(let ((n (dl-try-parse-int (slice s 5 (len s)))))
|
||||
(cond
|
||||
((nil? n) acc)
|
||||
((> n acc) n)
|
||||
(else acc))))
|
||||
(else acc))))
|
||||
((dict? term)
|
||||
(cond
|
||||
((has-key? term :neg)
|
||||
(dl-max-anon-num (get term :neg) acc))
|
||||
(else acc)))
|
||||
((list? term) (dl-max-anon-num-list term acc 0))
|
||||
(else acc))))
|
||||
|
||||
(define
|
||||
dl-max-anon-num-list
|
||||
(fn
|
||||
(xs acc i)
|
||||
(cond
|
||||
((>= i (len xs)) acc)
|
||||
(else
|
||||
(dl-max-anon-num-list xs (dl-max-anon-num (nth xs i) acc) (+ i 1))))))
|
||||
|
||||
;; Cheap "is this string a decimal int" check. Returns the number or
|
||||
;; nil. Avoids relying on host parse-number, which on non-int strings
|
||||
;; might raise rather than return nil.
|
||||
(define
|
||||
dl-try-parse-int
|
||||
(fn
|
||||
(s)
|
||||
(cond
|
||||
((= (len s) 0) nil)
|
||||
((not (dl-all-digits? s 0 (len s))) nil)
|
||||
(else (parse-number s)))))
|
||||
|
||||
(define
|
||||
dl-all-digits?
|
||||
(fn
|
||||
(s i n)
|
||||
(cond
|
||||
((>= i n) true)
|
||||
((let ((c (slice s i (+ i 1))))
|
||||
(not (and (>= c "0") (<= c "9"))))
|
||||
false)
|
||||
(else (dl-all-digits? s (+ i 1) n)))))
|
||||
|
||||
(define
|
||||
dl-rename-anon-rule
|
||||
(fn
|
||||
(rule)
|
||||
(let
|
||||
((start (dl-max-anon-num (get rule :head)
|
||||
(dl-max-anon-num-list (get rule :body) 0 0))))
|
||||
(let ((next-name (dl-make-anon-renamer start)))
|
||||
{:head (dl-rename-anon-term (get rule :head) next-name)
|
||||
:body (map (fn (lit) (dl-rename-anon-lit lit next-name))
|
||||
(get rule :body))}))))
|
||||
|
||||
(define
|
||||
dl-add-rule!
|
||||
(fn
|
||||
(db rule)
|
||||
(cond
|
||||
((not (dict? rule))
|
||||
(error (str "dl-add-rule!: expected rule dict, got " rule)))
|
||||
((not (has-key? rule :head))
|
||||
(error (str "dl-add-rule!: rule missing :head, got " rule)))
|
||||
((not (and (list? (get rule :head))
|
||||
(> (len (get rule :head)) 0)
|
||||
(symbol? (first (get rule :head)))))
|
||||
(error (str "dl-add-rule!: head must be a non-empty list "
|
||||
"starting with a relation-name symbol, got "
|
||||
(get rule :head))))
|
||||
((not (dl-args-simple? (get rule :head) 1 (len (get rule :head))))
|
||||
(error (str "dl-add-rule!: rule head args must be variables or "
|
||||
"constants — compound terms (e.g. `(*(X, 2))`) are "
|
||||
"not legal in head position; introduce an `is`-bound "
|
||||
"intermediate in the body. got " (get rule :head))))
|
||||
((not (list? (if (has-key? rule :body) (get rule :body) (list))))
|
||||
(error (str "dl-add-rule!: body must be a list of literals, got "
|
||||
(get rule :body))))
|
||||
((dl-reserved-rel? (dl-rel-name (get rule :head)))
|
||||
(error (str "dl-add-rule!: '" (dl-rel-name (get rule :head))
|
||||
"' is a reserved name (built-in / aggregate / negation)")))
|
||||
(else
|
||||
(let ((rule (dl-rename-anon-rule rule)))
|
||||
(let
|
||||
((err (dl-rule-check-safety rule)))
|
||||
(cond
|
||||
((not (nil? err)) (error (str "dl-add-rule!: " err)))
|
||||
(else
|
||||
(let
|
||||
((rules (get db :rules)))
|
||||
(do (append! rules rule) true))))))))))
|
||||
|
||||
(define
|
||||
dl-add-clause!
|
||||
(fn
|
||||
(db clause)
|
||||
(cond
|
||||
((has-key? clause :query) false)
|
||||
((and (has-key? clause :body) (= (len (get clause :body)) 0))
|
||||
(dl-add-fact! db (get clause :head)))
|
||||
(else (dl-add-rule! db clause)))))
|
||||
|
||||
(define
|
||||
dl-load-program!
|
||||
(fn
|
||||
(db source)
|
||||
(let
|
||||
((clauses (dl-parse source)))
|
||||
(do (for-each (fn (c) (dl-add-clause! db c)) clauses) db))))
|
||||
|
||||
(define
|
||||
dl-program
|
||||
(fn (source) (let ((db (dl-make-db))) (dl-load-program! db source))))
|
||||
|
||||
(define dl-rules (fn (db) (get db :rules)))
|
||||
|
||||
(define
|
||||
dl-fact-count
|
||||
(fn
|
||||
(db)
|
||||
(let
|
||||
((facts (get db :facts)) (total 0))
|
||||
(do
|
||||
(for-each
|
||||
(fn (k) (set! total (+ total (len (get facts k)))))
|
||||
(keys facts))
|
||||
total))))
|
||||
|
||||
;; Returns {<rel-name>: tuple-count} for debugging. Includes
|
||||
;; relations with any tuples plus all rule-head relations (so empty
|
||||
;; IDB shows as 0). Skips empty EDB-only entries that are placeholders
|
||||
;; from internal `dl-ensure-rel!` calls.
|
||||
(define
|
||||
dl-summary
|
||||
(fn
|
||||
(db)
|
||||
(let
|
||||
((facts (get db :facts))
|
||||
(out {})
|
||||
(rule-heads (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(rule)
|
||||
(let ((h (dl-rel-name (get rule :head))))
|
||||
(when
|
||||
(and (not (nil? h)) (not (dl-member-string? h rule-heads)))
|
||||
(append! rule-heads h))))
|
||||
(dl-rules db))
|
||||
(for-each
|
||||
(fn
|
||||
(k)
|
||||
(let ((c (len (get facts k))))
|
||||
(when
|
||||
(or (> c 0) (dl-member-string? k rule-heads))
|
||||
(dict-set! out k c))))
|
||||
(keys facts))
|
||||
;; Add rule heads that have no facts (yet).
|
||||
(for-each
|
||||
(fn
|
||||
(k)
|
||||
(when (not (has-key? out k)) (dict-set! out k 0)))
|
||||
rule-heads)
|
||||
out))))
|
||||
162
lib/datalog/demo.sx
Normal file
162
lib/datalog/demo.sx
Normal file
@@ -0,0 +1,162 @@
|
||||
;; lib/datalog/demo.sx — example programs over rose-ash-shaped data.
|
||||
;;
|
||||
;; Phase 10 prototypes Datalog as a rose-ash query language. Wiring
|
||||
;; the EDB to actual PostgreSQL is out of scope for this loop (it
|
||||
;; would touch service code outside lib/datalog/), but the programs
|
||||
;; below show the shape of queries we want, and the test suite runs
|
||||
;; them against synthetic in-memory tuples loaded via dl-program-data.
|
||||
;;
|
||||
;; Seven thematic demos:
|
||||
;;
|
||||
;; 1. Federation — follow graph, transitive reach, mutuals, FOAF.
|
||||
;; 2. Content — posts, tags, likes, popularity, "for you" feed.
|
||||
;; 3. Permissions — group membership and resource access.
|
||||
;; 4. Cooking-posts — canonical "posts about cooking by people I
|
||||
;; follow (transitively)" multi-domain query.
|
||||
;; 5. Tag co-occurrence — distinct (T1, T2) pairs with counts.
|
||||
;; 6. Shortest path — weighted-DAG path enumeration + min agg.
|
||||
;; 7. Org chart — transitive subordinate + headcount per mgr.
|
||||
|
||||
;; ── Demo 1: federation follow graph ─────────────────────────────
|
||||
;; EDB: (follows ACTOR-A ACTOR-B) — A follows B.
|
||||
;; IDB:
|
||||
;; (mutual A B) — A follows B and B follows A
|
||||
;; (reachable A B) — transitive follow closure
|
||||
;; (foaf A C) — friend of a friend (mutual filter)
|
||||
(define
|
||||
dl-demo-federation-rules
|
||||
(quote
|
||||
((mutual A B <- (follows A B) (follows B A))
|
||||
(reachable A B <- (follows A B))
|
||||
(reachable A C <- (follows A B) (reachable B C))
|
||||
(foaf A C <- (follows A B) (follows B C) (!= A C)))))
|
||||
|
||||
;; ── Demo 2: content recommendation ──────────────────────────────
|
||||
;; EDB:
|
||||
;; (authored ACTOR POST)
|
||||
;; (tagged POST TAG)
|
||||
;; (liked ACTOR POST)
|
||||
;; IDB:
|
||||
;; (post-likes POST N) — count of likes per post
|
||||
;; (popular POST) — posts with >= 3 likes
|
||||
;; (tagged-by-mutual ACTOR POST) — post tagged TOPIC by someone
|
||||
;; A's mutuals follow.
|
||||
(define
|
||||
dl-demo-content-rules
|
||||
(quote
|
||||
((post-likes P N <- (authored Author P) (count N L (liked L P)))
|
||||
(popular P <- (authored Author P) (post-likes P N) (>= N 3))
|
||||
(interesting Me P
|
||||
<-
|
||||
(follows Me Buddy)
|
||||
(authored Buddy P)
|
||||
(popular P)))))
|
||||
|
||||
;; ── Demo 3: role-based permissions ──────────────────────────────
|
||||
;; EDB:
|
||||
;; (member ACTOR GROUP)
|
||||
;; (subgroup CHILD PARENT)
|
||||
;; (allowed GROUP RESOURCE)
|
||||
;; IDB:
|
||||
;; (in-group ACTOR GROUP) — direct or via subgroup chain
|
||||
;; (can-access ACTOR RESOURCE) — actor inherits group permission
|
||||
(define
|
||||
dl-demo-perm-rules
|
||||
(quote
|
||||
((in-group A G <- (member A G))
|
||||
(in-group A G <- (member A H) (subgroup-trans H G))
|
||||
(subgroup-trans X Y <- (subgroup X Y))
|
||||
(subgroup-trans X Z <- (subgroup X Y) (subgroup-trans Y Z))
|
||||
(can-access A R <- (in-group A G) (allowed G R)))))
|
||||
|
||||
;; ── Demo 4: cooking-posts (the canonical Phase 10 query) ────────
|
||||
;; "Posts about cooking by people I follow (transitively)."
|
||||
;; Combines federation (follows + transitive reach), authoring,
|
||||
;; tagging — the rose-ash multi-domain join.
|
||||
;;
|
||||
;; EDB:
|
||||
;; (follows ACTOR-A ACTOR-B)
|
||||
;; (authored ACTOR POST)
|
||||
;; (tagged POST TAG)
|
||||
(define
|
||||
dl-demo-cooking-rules
|
||||
(quote
|
||||
((reach Me Them <- (follows Me Them))
|
||||
(reach Me Them <- (follows Me X) (reach X Them))
|
||||
(cooking-post-by-network Me P
|
||||
<-
|
||||
(reach Me Author)
|
||||
(authored Author P)
|
||||
(tagged P cooking)))))
|
||||
|
||||
;; ── Demo 5: tag co-occurrence ───────────────────────────────────
|
||||
;; "Posts tagged with both T1 AND T2." Useful for narrowed-down
|
||||
;; recommendations like "vegetarian cooking" posts.
|
||||
;;
|
||||
;; EDB:
|
||||
;; (tagged POST TAG)
|
||||
;; IDB:
|
||||
;; (cotagged POST T1 T2) — post has both T1 and T2 (T1 != T2)
|
||||
;; (popular-pair T1 T2 N) — count of posts cotagged (T1, T2)
|
||||
(define
|
||||
dl-demo-tag-cooccur-rules
|
||||
(quote
|
||||
((cotagged P T1 T2 <- (tagged P T1) (tagged P T2) (!= T1 T2))
|
||||
;; Distinct (T1, T2) pairs that occur somewhere.
|
||||
(tag-pair T1 T2 <- (cotagged P T1 T2))
|
||||
(tag-pair-count T1 T2 N
|
||||
<-
|
||||
(tag-pair T1 T2)
|
||||
(count N P (cotagged P T1 T2))))))
|
||||
|
||||
;; ── Demo 6: weighted-DAG shortest path ─────────────────────────
|
||||
;; "What's the cheapest way from X to Y?" Edge weights with `is`
|
||||
;; arithmetic to sum costs, then `min` aggregation to pick the
|
||||
;; shortest. Termination requires the graph to be a DAG (cycles
|
||||
;; would produce infinite distances without a bound; programs
|
||||
;; built on this should add a depth filter `(<, D, MAX)` if cycles
|
||||
;; are possible).
|
||||
;;
|
||||
;; EDB:
|
||||
;; (edge FROM TO COST)
|
||||
;; IDB:
|
||||
;; (path FROM TO COST) — any path
|
||||
;; (shortest FROM TO COST) — minimum cost path
|
||||
(define
|
||||
dl-demo-shortest-path-rules
|
||||
(quote
|
||||
((path X Y W <- (edge X Y W))
|
||||
(path X Z W
|
||||
<-
|
||||
(edge X Y W1)
|
||||
(path Y Z W2)
|
||||
(is W (+ W1 W2)))
|
||||
(shortest X Y W <- (path X Y _) (min W C (path X Y C))))))
|
||||
|
||||
;; ── Demo 7: org chart + transitive headcount ───────────────────
|
||||
;; Manager graph: each employee has a single manager. Compute the
|
||||
;; transitive subordinate set and headcount per manager.
|
||||
;;
|
||||
;; EDB:
|
||||
;; (manager EMP MGR) — EMP reports directly to MGR
|
||||
;; IDB:
|
||||
;; (subordinate MGR EMP) — EMP is in MGR's subtree
|
||||
;; (headcount MGR N) — number of subordinates under MGR
|
||||
(define
|
||||
dl-demo-org-rules
|
||||
(quote
|
||||
((subordinate Mgr Emp <- (manager Emp Mgr))
|
||||
(subordinate Mgr Emp
|
||||
<- (manager Mid Mgr) (subordinate Mid Emp))
|
||||
(headcount Mgr N
|
||||
<- (subordinate Mgr Anyone) (count N E (subordinate Mgr E))))))
|
||||
|
||||
;; ── Loader stub ──────────────────────────────────────────────────
|
||||
;; Wiring to PostgreSQL would replace these helpers with calls into
|
||||
;; rose-ash's internal HTTP RPC (fetch_data → /internal/data/...).
|
||||
;; The shape returned by dl-load-from-edb! is the same in either case.
|
||||
(define
|
||||
dl-demo-make
|
||||
(fn
|
||||
(facts rules)
|
||||
(dl-program-data facts rules)))
|
||||
512
lib/datalog/eval.sx
Normal file
512
lib/datalog/eval.sx
Normal file
@@ -0,0 +1,512 @@
|
||||
;; lib/datalog/eval.sx — fixpoint evaluator (naive + semi-naive).
|
||||
;;
|
||||
;; Two saturators are exposed:
|
||||
;; `dl-saturate-naive!` — re-joins each rule against the full DB every
|
||||
;; iteration. Reference implementation; useful for differential tests.
|
||||
;; `dl-saturate!` — semi-naive default. Tracks per-relation delta
|
||||
;; sets and substitutes one positive body literal per rule with the
|
||||
;; delta of its relation, joining the rest against the previous-
|
||||
;; iteration DB. Same fixpoint, dramatically less work on recursive
|
||||
;; rules.
|
||||
;;
|
||||
;; Body literal kinds:
|
||||
;; positive (rel arg ... arg) → match against EDB+IDB tuples
|
||||
;; built-in (< X Y), (is X e) → constraint via dl-eval-builtin
|
||||
;; negation {:neg lit} → Phase 7
|
||||
|
||||
(define
|
||||
dl-match-positive
|
||||
(fn
|
||||
(lit db subst)
|
||||
(let
|
||||
((rel (dl-rel-name lit)) (results (list)))
|
||||
(cond
|
||||
((nil? rel) (error (str "dl-match-positive: bad literal " lit)))
|
||||
(else
|
||||
(let
|
||||
;; If the first argument walks to a non-variable (constant
|
||||
;; or already-bound var), use the first-arg index for
|
||||
;; this relation. Otherwise scan the full tuple list.
|
||||
((tuples
|
||||
(cond
|
||||
((>= (len lit) 2)
|
||||
(let ((walked (dl-walk (nth lit 1) subst)))
|
||||
(cond
|
||||
((dl-var? walked) (dl-rel-tuples db rel))
|
||||
(else (dl-index-lookup db rel walked)))))
|
||||
(else (dl-rel-tuples db rel)))))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(tuple)
|
||||
(let
|
||||
((s (dl-unify lit tuple subst)))
|
||||
(when (not (nil? s)) (append! results s))))
|
||||
tuples)
|
||||
results)))))))
|
||||
|
||||
;; Match a positive literal against the delta set for its relation only.
|
||||
(define
|
||||
dl-match-positive-delta
|
||||
(fn
|
||||
(lit delta subst)
|
||||
(let
|
||||
((rel (dl-rel-name lit)) (results (list)))
|
||||
(let
|
||||
((tuples (if (has-key? delta rel) (get delta rel) (list))))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(tuple)
|
||||
(let
|
||||
((s (dl-unify lit tuple subst)))
|
||||
(when (not (nil? s)) (append! results s))))
|
||||
tuples)
|
||||
results)))))
|
||||
|
||||
;; Naive matcher (for dl-saturate-naive! and dl-query post-saturation).
|
||||
(define
|
||||
dl-match-negation
|
||||
(fn
|
||||
(inner db subst)
|
||||
(let
|
||||
((walked (dl-apply-subst inner subst))
|
||||
(matches (dl-match-positive inner db subst)))
|
||||
(cond
|
||||
((= (len matches) 0) (list subst))
|
||||
(else (list))))))
|
||||
|
||||
(define
|
||||
dl-match-lit
|
||||
(fn
|
||||
(lit db subst)
|
||||
(cond
|
||||
((and (dict? lit) (has-key? lit :neg))
|
||||
(dl-match-negation (get lit :neg) db subst))
|
||||
((dl-aggregate? lit) (dl-eval-aggregate lit db subst))
|
||||
((dl-builtin? lit)
|
||||
(let
|
||||
((s (dl-eval-builtin lit subst)))
|
||||
(if (nil? s) (list) (list s))))
|
||||
((and (list? lit) (> (len lit) 0))
|
||||
(dl-match-positive lit db subst))
|
||||
(else (error (str "datalog: unknown body-literal shape: " lit))))))
|
||||
|
||||
(define
|
||||
dl-find-bindings
|
||||
(fn (lits db subst) (dl-fb-aux lits db subst 0 (len lits))))
|
||||
|
||||
(define
|
||||
dl-fb-aux
|
||||
(fn
|
||||
(lits db subst i n)
|
||||
(cond
|
||||
((nil? subst) (list))
|
||||
((>= i n) (list subst))
|
||||
(else
|
||||
(let
|
||||
((options (dl-match-lit (nth lits i) db subst))
|
||||
(results (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(s)
|
||||
(for-each
|
||||
(fn (s2) (append! results s2))
|
||||
(dl-fb-aux lits db s (+ i 1) n)))
|
||||
options)
|
||||
results))))))
|
||||
|
||||
;; Naive: apply each rule against full DB until no new tuples.
|
||||
(define
|
||||
dl-apply-rule!
|
||||
(fn
|
||||
(db rule)
|
||||
(let
|
||||
((head (get rule :head)) (body (get rule :body)) (new? false))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(s)
|
||||
(let
|
||||
((derived (dl-apply-subst head s)))
|
||||
(when (dl-add-derived! db derived) (set! new? true))))
|
||||
(dl-find-bindings body db (dl-empty-subst)))
|
||||
new?))))
|
||||
|
||||
;; Returns true iff one more saturation step would derive no new
|
||||
;; tuples (i.e. the db is at fixpoint). Useful in tests that want
|
||||
;; to assert "no work left" after a saturation call. Works under
|
||||
;; either saturator since both compute the same fixpoint.
|
||||
(define
|
||||
dl-saturated?
|
||||
(fn
|
||||
(db)
|
||||
(let ((any-new false))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(rule)
|
||||
(when (not any-new)
|
||||
(for-each
|
||||
(fn
|
||||
(s)
|
||||
(let ((derived (dl-apply-subst (get rule :head) s)))
|
||||
(when
|
||||
(and (not any-new)
|
||||
(not (dl-tuple-member?
|
||||
derived
|
||||
(dl-rel-tuples
|
||||
db (dl-rel-name derived)))))
|
||||
(set! any-new true))))
|
||||
(dl-find-bindings (get rule :body) db (dl-empty-subst)))))
|
||||
(dl-rules db))
|
||||
(not any-new)))))
|
||||
|
||||
(define
|
||||
dl-saturate-naive!
|
||||
(fn
|
||||
(db)
|
||||
(let
|
||||
((changed true))
|
||||
(do
|
||||
(define
|
||||
dl-snloop
|
||||
(fn
|
||||
()
|
||||
(when
|
||||
changed
|
||||
(do
|
||||
(set! changed false)
|
||||
(for-each
|
||||
(fn (r) (when (dl-apply-rule! db r) (set! changed true)))
|
||||
(dl-rules db))
|
||||
(dl-snloop)))))
|
||||
(dl-snloop)
|
||||
db))))
|
||||
|
||||
;; ── Semi-naive ───────────────────────────────────────────────────
|
||||
|
||||
;; Take a snapshot dict {rel -> tuples} of every relation currently in
|
||||
;; the DB. Used as initial delta for the first iteration.
|
||||
(define
|
||||
dl-snapshot-facts
|
||||
(fn
|
||||
(db)
|
||||
(let
|
||||
((facts (get db :facts)) (out {}))
|
||||
(do
|
||||
(for-each
|
||||
(fn (k) (dict-set! out k (dl-copy-list (get facts k))))
|
||||
(keys facts))
|
||||
out))))
|
||||
|
||||
(define
|
||||
dl-copy-list
|
||||
(fn
|
||||
(xs)
|
||||
(let
|
||||
((out (list)))
|
||||
(do (for-each (fn (x) (append! out x)) xs) out))))
|
||||
|
||||
;; Does any relation in `delta` have ≥1 tuple?
|
||||
(define
|
||||
dl-delta-empty?
|
||||
(fn
|
||||
(delta)
|
||||
(let
|
||||
((ks (keys delta)) (any-non-empty false))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(k)
|
||||
(when
|
||||
(> (len (get delta k)) 0)
|
||||
(set! any-non-empty true)))
|
||||
ks)
|
||||
(not any-non-empty)))))
|
||||
|
||||
;; Find substitutions such that `lits` are all satisfied AND `delta-idx`
|
||||
;; is matched against the per-relation delta only. The other positive
|
||||
;; literals match against the snapshot DB (db.facts read at iteration
|
||||
;; start). Built-ins and negations behave as in `dl-match-lit`.
|
||||
(define
|
||||
dl-find-bindings-semi
|
||||
(fn
|
||||
(lits db delta delta-idx subst)
|
||||
(dl-fbs-aux lits db delta delta-idx 0 subst)))
|
||||
|
||||
(define
|
||||
dl-fbs-aux
|
||||
(fn
|
||||
(lits db delta delta-idx i subst)
|
||||
(cond
|
||||
((nil? subst) (list))
|
||||
((>= i (len lits)) (list subst))
|
||||
(else
|
||||
(let
|
||||
((lit (nth lits i))
|
||||
(options
|
||||
(cond
|
||||
((and (dict? lit) (has-key? lit :neg))
|
||||
(dl-match-negation (get lit :neg) db subst))
|
||||
((dl-aggregate? lit) (dl-eval-aggregate lit db subst))
|
||||
((dl-builtin? lit)
|
||||
(let
|
||||
((s (dl-eval-builtin lit subst)))
|
||||
(if (nil? s) (list) (list s))))
|
||||
((and (list? lit) (> (len lit) 0))
|
||||
(if
|
||||
(= i delta-idx)
|
||||
(dl-match-positive-delta lit delta subst)
|
||||
(dl-match-positive lit db subst)))
|
||||
(else (error (str "datalog: unknown body-lit: " lit)))))
|
||||
(results (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(s)
|
||||
(for-each
|
||||
(fn (s2) (append! results s2))
|
||||
(dl-fbs-aux lits db delta delta-idx (+ i 1) s)))
|
||||
options)
|
||||
results))))))
|
||||
|
||||
;; Collect candidate head tuples from a rule using delta. Walks every
|
||||
;; positive body position and unions the resulting heads. For rules
|
||||
;; with no positive body literal, falls back to a naive single-pass
|
||||
;; (so static facts like `(p X) :- (= X 5).` derive on iteration 1).
|
||||
(define
|
||||
dl-collect-rule-candidates
|
||||
(fn
|
||||
(rule db delta)
|
||||
(let
|
||||
((head (get rule :head))
|
||||
(body (get rule :body))
|
||||
(out (list))
|
||||
(saw-pos false))
|
||||
(do
|
||||
(define
|
||||
dl-cri
|
||||
(fn
|
||||
(i)
|
||||
(when
|
||||
(< i (len body))
|
||||
(do
|
||||
(let
|
||||
((lit (nth body i)))
|
||||
(when
|
||||
(dl-positive-lit? lit)
|
||||
(do
|
||||
(set! saw-pos true)
|
||||
(for-each
|
||||
(fn (s) (append! out (dl-apply-subst head s)))
|
||||
(dl-find-bindings-semi
|
||||
body
|
||||
db
|
||||
delta
|
||||
i
|
||||
(dl-empty-subst))))))
|
||||
(dl-cri (+ i 1))))))
|
||||
(dl-cri 0)
|
||||
(when
|
||||
(not saw-pos)
|
||||
(for-each
|
||||
(fn (s) (append! out (dl-apply-subst head s)))
|
||||
(dl-find-bindings body db (dl-empty-subst))))
|
||||
out))))
|
||||
|
||||
;; Add a list of candidate tuples to db; collect newly-added ones into
|
||||
;; the new-delta dict (keyed by relation name).
|
||||
(define
|
||||
dl-commit-candidates!
|
||||
(fn
|
||||
(db candidates new-delta)
|
||||
(for-each
|
||||
(fn
|
||||
(lit)
|
||||
(when
|
||||
(dl-add-derived! db lit)
|
||||
(let
|
||||
((rel (dl-rel-name lit)))
|
||||
(do
|
||||
(when
|
||||
(not (has-key? new-delta rel))
|
||||
(dict-set! new-delta rel (list)))
|
||||
(append! (get new-delta rel) lit)))))
|
||||
candidates)))
|
||||
|
||||
(define
|
||||
dl-saturate-rules!
|
||||
(fn
|
||||
(db rules)
|
||||
(let
|
||||
((delta (dl-snapshot-facts db)))
|
||||
(do
|
||||
(define
|
||||
dl-sr-step
|
||||
(fn
|
||||
()
|
||||
(let
|
||||
((pending (list)) (new-delta {}))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(rule)
|
||||
(for-each
|
||||
(fn (cand) (append! pending cand))
|
||||
(dl-collect-rule-candidates rule db delta)))
|
||||
rules)
|
||||
(dl-commit-candidates! db pending new-delta)
|
||||
(cond
|
||||
((dl-delta-empty? new-delta) nil)
|
||||
(else (do (set! delta new-delta) (dl-sr-step))))))))
|
||||
(dl-sr-step)
|
||||
db))))
|
||||
|
||||
;; Stratified driver: rejects non-stratifiable programs at saturation
|
||||
;; time, then iterates strata in increasing order, running semi-naive on
|
||||
;; the rules whose head sits in that stratum.
|
||||
(define
|
||||
dl-saturate!
|
||||
(fn
|
||||
(db)
|
||||
(let
|
||||
((err (dl-check-stratifiable db)))
|
||||
(cond
|
||||
((not (nil? err)) (error (str "dl-saturate!: " err)))
|
||||
(else
|
||||
(let
|
||||
((strata (dl-compute-strata db)))
|
||||
(let
|
||||
((grouped (dl-group-rules-by-stratum db strata)))
|
||||
(let
|
||||
((groups (get grouped :groups))
|
||||
(max-s (get grouped :max)))
|
||||
(do
|
||||
(define
|
||||
dl-strat-loop
|
||||
(fn
|
||||
(s)
|
||||
(when
|
||||
(<= s max-s)
|
||||
(let
|
||||
((sk (str s)))
|
||||
(do
|
||||
(when
|
||||
(has-key? groups sk)
|
||||
(dl-saturate-rules! db (get groups sk)))
|
||||
(dl-strat-loop (+ s 1)))))))
|
||||
(dl-strat-loop 0)
|
||||
db)))))))))
|
||||
|
||||
;; ── Querying ─────────────────────────────────────────────────────
|
||||
|
||||
;; Coerce a query argument to a list of body literals. A single literal
|
||||
;; like `(p X)` (positive — head is a symbol) or `{:neg ...}` becomes
|
||||
;; `((p X))`. A list of literals like `((p X) (q X))` is returned as-is.
|
||||
(define
|
||||
dl-query-coerce
|
||||
(fn
|
||||
(goal)
|
||||
(cond
|
||||
((and (dict? goal) (has-key? goal :neg)) (list goal))
|
||||
((and (list? goal) (> (len goal) 0) (symbol? (first goal)))
|
||||
(list goal))
|
||||
((list? goal) goal)
|
||||
(else (error (str "dl-query: unrecognised goal shape: " goal))))))
|
||||
|
||||
(define
|
||||
dl-query
|
||||
(fn
|
||||
(db goal)
|
||||
(do
|
||||
(dl-saturate! db)
|
||||
;; Rename anonymous '_' vars in each goal literal so multiple
|
||||
;; occurrences do not unify together. Keep the user-facing var
|
||||
;; list (taken before renaming) so projected results retain user
|
||||
;; names.
|
||||
(let
|
||||
((goals (dl-query-coerce goal))
|
||||
;; Start the renamer past any `_anon<N>` symbols the user
|
||||
;; may have written in the query — avoids collision.
|
||||
(renamer
|
||||
(dl-make-anon-renamer (dl-max-anon-num-list goal 0 0))))
|
||||
(let
|
||||
((user-vars (dl-query-user-vars goals))
|
||||
(renamed (map (fn (g) (dl-rename-anon-lit g renamer)) goals)))
|
||||
(let
|
||||
((substs (dl-find-bindings renamed db (dl-empty-subst)))
|
||||
(results (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(s)
|
||||
(let
|
||||
((proj (dl-project-subst s user-vars)))
|
||||
(when
|
||||
(not (dl-tuple-member? proj results))
|
||||
(append! results proj))))
|
||||
substs)
|
||||
results)))))))
|
||||
|
||||
(define
|
||||
dl-query-user-vars
|
||||
(fn
|
||||
(goals)
|
||||
(let ((seen (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(g)
|
||||
(cond
|
||||
((and (dict? g) (has-key? g :neg))
|
||||
(for-each
|
||||
(fn
|
||||
(v)
|
||||
(when
|
||||
(and (not (= v "_")) (not (dl-member-string? v seen)))
|
||||
(append! seen v)))
|
||||
(dl-vars-of (get g :neg))))
|
||||
((dl-aggregate? g)
|
||||
;; Only the result var (first arg of the aggregate
|
||||
;; literal) is user-facing. The aggregated var and
|
||||
;; any vars in the inner goal are internal.
|
||||
(let ((r (nth g 1)))
|
||||
(when
|
||||
(dl-var? r)
|
||||
(let ((rn (symbol->string r)))
|
||||
(when
|
||||
(and (not (= rn "_"))
|
||||
(not (dl-member-string? rn seen)))
|
||||
(append! seen rn))))))
|
||||
(else
|
||||
(for-each
|
||||
(fn
|
||||
(v)
|
||||
(when
|
||||
(and (not (= v "_")) (not (dl-member-string? v seen)))
|
||||
(append! seen v)))
|
||||
(dl-vars-of g)))))
|
||||
goals)
|
||||
seen))))
|
||||
|
||||
(define
|
||||
dl-project-subst
|
||||
(fn
|
||||
(subst names)
|
||||
(let
|
||||
((out {}))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(n)
|
||||
(let
|
||||
((sym (string->symbol n)))
|
||||
(let
|
||||
((v (dl-walk sym subst)))
|
||||
(dict-set! out n (dl-apply-subst v subst)))))
|
||||
names)
|
||||
out))))
|
||||
|
||||
(define dl-relation (fn (db name) (dl-rel-tuples db name)))
|
||||
464
lib/datalog/magic.sx
Normal file
464
lib/datalog/magic.sx
Normal file
@@ -0,0 +1,464 @@
|
||||
;; lib/datalog/magic.sx — adornment analysis + sideways info passing.
|
||||
;;
|
||||
;; First step of the magic-sets transformation (Phase 6). Right now
|
||||
;; the saturator does not consume these — they are introspection
|
||||
;; helpers that future magic-set rewriting will build on top of.
|
||||
;;
|
||||
;; Definitions:
|
||||
;; - An *adornment* of an n-ary literal is an n-character string
|
||||
;; of "b" (bound — value already known at the call site) and
|
||||
;; "f" (free — to be derived).
|
||||
;; - SIPS (Sideways Information Passing Strategy) walks the body
|
||||
;; of an adorned rule left-to-right tracking which variables
|
||||
;; have been bound so far, computing each body literal's
|
||||
;; adornment in turn.
|
||||
;;
|
||||
;; Usage:
|
||||
;;
|
||||
;; (dl-adorn-goal '(ancestor tom X))
|
||||
;; => "bf"
|
||||
;;
|
||||
;; (dl-rule-sips
|
||||
;; {:head (ancestor X Z)
|
||||
;; :body ((parent X Y) (ancestor Y Z))}
|
||||
;; "bf")
|
||||
;; => ({:lit (parent X Y) :adornment "bf"}
|
||||
;; {:lit (ancestor Y Z) :adornment "bf"})
|
||||
|
||||
;; Per-arg adornment under the current bound-var name set.
|
||||
(define
|
||||
dl-adorn-arg
|
||||
(fn
|
||||
(arg bound)
|
||||
(cond
|
||||
((dl-var? arg)
|
||||
(if (dl-member-string? (symbol->string arg) bound) "b" "f"))
|
||||
(else "b"))))
|
||||
|
||||
;; Adornment for the args of a literal (after the relation name).
|
||||
(define
|
||||
dl-adorn-args
|
||||
(fn
|
||||
(args bound)
|
||||
(cond
|
||||
((= (len args) 0) "")
|
||||
(else
|
||||
(str
|
||||
(dl-adorn-arg (first args) bound)
|
||||
(dl-adorn-args (rest args) bound))))))
|
||||
|
||||
;; Adornment of a top-level goal under the empty bound-var set.
|
||||
(define
|
||||
dl-adorn-goal
|
||||
(fn (goal) (dl-adorn-args (rest goal) (list))))
|
||||
|
||||
;; Adornment of a literal under an explicit bound set.
|
||||
(define
|
||||
dl-adorn-lit
|
||||
(fn (lit bound) (dl-adorn-args (rest lit) bound)))
|
||||
|
||||
;; The set of variable names made bound by walking a positive
|
||||
;; literal whose adornment is known. Free positions add their
|
||||
;; vars to the bound set.
|
||||
(define
|
||||
dl-vars-bound-by-lit
|
||||
(fn
|
||||
(lit bound)
|
||||
(let ((args (rest lit)) (out (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn (a)
|
||||
(when
|
||||
(and (dl-var? a)
|
||||
(not (dl-member-string? (symbol->string a) bound))
|
||||
(not (dl-member-string? (symbol->string a) out)))
|
||||
(append! out (symbol->string a))))
|
||||
args)
|
||||
out))))
|
||||
|
||||
;; Walk the rule body left-to-right tracking bound vars seeded by the
|
||||
;; head adornment. Returns a list of {:lit :adornment} entries.
|
||||
;;
|
||||
;; Negation, comparison, and built-ins are passed through with their
|
||||
;; adornment computed from the current bound set; they don't add new
|
||||
;; bindings (except `is`, which binds its left arg if a var). Aggregates
|
||||
;; are treated like is — the result var becomes bound.
|
||||
(define
|
||||
dl-init-head-bound
|
||||
(fn
|
||||
(head adornment)
|
||||
(let ((args (rest head)) (out (list)))
|
||||
(do
|
||||
(define
|
||||
dl-ihb-loop
|
||||
(fn
|
||||
(i)
|
||||
(when
|
||||
(< i (len args))
|
||||
(do
|
||||
(let
|
||||
((c (slice adornment i (+ i 1)))
|
||||
(a (nth args i)))
|
||||
(when
|
||||
(and (= c "b") (dl-var? a))
|
||||
(let ((n (symbol->string a)))
|
||||
(when
|
||||
(not (dl-member-string? n out))
|
||||
(append! out n)))))
|
||||
(dl-ihb-loop (+ i 1))))))
|
||||
(dl-ihb-loop 0)
|
||||
out))))
|
||||
|
||||
(define
|
||||
dl-rule-sips
|
||||
(fn
|
||||
(rule head-adornment)
|
||||
(let
|
||||
((bound (dl-init-head-bound (get rule :head) head-adornment))
|
||||
(out (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(lit)
|
||||
(cond
|
||||
((and (dict? lit) (has-key? lit :neg))
|
||||
(let ((target (get lit :neg)))
|
||||
(append!
|
||||
out
|
||||
{:lit lit :adornment (dl-adorn-lit target bound)})))
|
||||
((dl-builtin? lit)
|
||||
(let ((adn (dl-adorn-lit lit bound)))
|
||||
(do
|
||||
(append! out {:lit lit :adornment adn})
|
||||
;; `is` binds its left arg (if var) once RHS is ground.
|
||||
(when
|
||||
(and (= (dl-rel-name lit) "is") (dl-var? (nth lit 1)))
|
||||
(let ((n (symbol->string (nth lit 1))))
|
||||
(when
|
||||
(not (dl-member-string? n bound))
|
||||
(append! bound n)))))))
|
||||
((and (list? lit) (dl-aggregate? lit))
|
||||
(let ((adn (dl-adorn-lit lit bound)))
|
||||
(do
|
||||
(append! out {:lit lit :adornment adn})
|
||||
;; Result var (first arg) becomes bound.
|
||||
(when (dl-var? (nth lit 1))
|
||||
(let ((n (symbol->string (nth lit 1))))
|
||||
(when
|
||||
(not (dl-member-string? n bound))
|
||||
(append! bound n)))))))
|
||||
((and (list? lit) (> (len lit) 0))
|
||||
(let ((adn (dl-adorn-lit lit bound)))
|
||||
(do
|
||||
(append! out {:lit lit :adornment adn})
|
||||
(for-each
|
||||
(fn (n)
|
||||
(when (not (dl-member-string? n bound))
|
||||
(append! bound n)))
|
||||
(dl-vars-bound-by-lit lit bound)))))))
|
||||
(get rule :body))
|
||||
out))))
|
||||
|
||||
;; ── Magic predicate naming + bound-args extraction ─────────────
|
||||
;; These are building blocks for the magic-sets *transformation*
|
||||
;; itself. The transformation (which generates rewritten rules
|
||||
;; with magic_<rel>^<adornment> filters) is future work — for now
|
||||
;; these helpers can be used to inspect what such a transformation
|
||||
;; would produce.
|
||||
|
||||
;; "magic_p^bf" given relation "p" and adornment "bf".
|
||||
(define
|
||||
dl-magic-rel-name
|
||||
(fn (rel adornment) (str "magic_" rel "^" adornment)))
|
||||
|
||||
;; A magic predicate literal:
|
||||
;; (magic_<rel>^<adornment> arg1 arg2 ...)
|
||||
(define
|
||||
dl-magic-lit
|
||||
(fn
|
||||
(rel adornment bound-args)
|
||||
(cons (string->symbol (dl-magic-rel-name rel adornment)) bound-args)))
|
||||
|
||||
;; Extract bound args (those at "b" positions in `adornment`) from a
|
||||
;; literal `(rel arg1 arg2 ... argN)`. Returns the list of arg values.
|
||||
(define
|
||||
dl-bound-args
|
||||
(fn
|
||||
(lit adornment)
|
||||
(let ((args (rest lit)) (out (list)))
|
||||
(do
|
||||
(define
|
||||
dl-ba-loop
|
||||
(fn
|
||||
(i)
|
||||
(when
|
||||
(< i (len args))
|
||||
(do
|
||||
(when
|
||||
(= (slice adornment i (+ i 1)) "b")
|
||||
(append! out (nth args i)))
|
||||
(dl-ba-loop (+ i 1))))))
|
||||
(dl-ba-loop 0)
|
||||
out))))
|
||||
|
||||
;; ── Magic-sets rewriter ─────────────────────────────────────────
|
||||
;;
|
||||
;; Given the original rule list and a query (rel, adornment) pair,
|
||||
;; generates the magic-rewritten program: a list of rules that
|
||||
;; (a) gate each original rule with a `magic_<rel>^<adn>` filter and
|
||||
;; (b) propagate the magic relation through SIPS so that only
|
||||
;; query-relevant tuples are derived. Seed facts are returned
|
||||
;; separately and must be added to the db at evaluation time.
|
||||
;;
|
||||
;; Output: {:rules <rewritten-rules> :seed <magic-seed-literal>}
|
||||
;;
|
||||
;; The rewriter only rewrites IDB rules; EDB facts pass through.
|
||||
;; Built-in predicates and negation in body literals are kept in
|
||||
;; place but do not generate propagation rules of their own.
|
||||
|
||||
(define
|
||||
dl-magic-pair-key
|
||||
(fn (rel adornment) (str rel "^" adornment)))
|
||||
|
||||
(define
|
||||
dl-magic-rewrite
|
||||
(fn
|
||||
(rules query-rel query-adornment query-args)
|
||||
(let
|
||||
((seen (list))
|
||||
(queue (list))
|
||||
(out (list)))
|
||||
(do
|
||||
(define
|
||||
dl-mq-mark!
|
||||
(fn
|
||||
(rel adornment)
|
||||
(let ((k (dl-magic-pair-key rel adornment)))
|
||||
(when
|
||||
(not (dl-member-string? k seen))
|
||||
(do
|
||||
(append! seen k)
|
||||
(append! queue {:rel rel :adn adornment}))))))
|
||||
|
||||
(define
|
||||
dl-mq-rewrite-rule!
|
||||
(fn
|
||||
(rule adn)
|
||||
(let
|
||||
((head (get rule :head))
|
||||
(body (get rule :body))
|
||||
(sips (dl-rule-sips rule adn)))
|
||||
(let
|
||||
((magic-filter
|
||||
(dl-magic-lit
|
||||
(dl-rel-name head)
|
||||
adn
|
||||
(dl-bound-args head adn))))
|
||||
(do
|
||||
;; Adorned rule: head :- magic-filter, body...
|
||||
(let ((new-body (list)))
|
||||
(do
|
||||
(append! new-body magic-filter)
|
||||
(for-each
|
||||
(fn (lit) (append! new-body lit))
|
||||
body)
|
||||
(append! out {:head head :body new-body})))
|
||||
;; Propagation rules for each positive non-builtin
|
||||
;; body literal at position i.
|
||||
(define
|
||||
dl-mq-prop-loop
|
||||
(fn
|
||||
(i)
|
||||
(when
|
||||
(< i (len body))
|
||||
(do
|
||||
(let
|
||||
((lit (nth body i))
|
||||
(sip-entry (nth sips i)))
|
||||
(when
|
||||
(and (list? lit)
|
||||
(> (len lit) 0)
|
||||
(not (and (dict? lit) (has-key? lit :neg)))
|
||||
(not (dl-builtin? lit))
|
||||
(not (dl-aggregate? lit)))
|
||||
(let
|
||||
((lit-adn (get sip-entry :adornment))
|
||||
(lit-rel (dl-rel-name lit)))
|
||||
(let
|
||||
((prop-head
|
||||
(dl-magic-lit
|
||||
lit-rel
|
||||
lit-adn
|
||||
(dl-bound-args lit lit-adn))))
|
||||
(let ((prop-body (list)))
|
||||
(do
|
||||
(append! prop-body magic-filter)
|
||||
(define
|
||||
dl-mq-prefix-loop
|
||||
(fn
|
||||
(j)
|
||||
(when
|
||||
(< j i)
|
||||
(do
|
||||
(append!
|
||||
prop-body
|
||||
(nth body j))
|
||||
(dl-mq-prefix-loop (+ j 1))))))
|
||||
(dl-mq-prefix-loop 0)
|
||||
(append!
|
||||
out
|
||||
{:head prop-head :body prop-body})
|
||||
(dl-mq-mark! lit-rel lit-adn)))))))
|
||||
(dl-mq-prop-loop (+ i 1))))))
|
||||
(dl-mq-prop-loop 0))))))
|
||||
|
||||
(dl-mq-mark! query-rel query-adornment)
|
||||
|
||||
(let ((idx 0))
|
||||
(define
|
||||
dl-mq-process
|
||||
(fn
|
||||
()
|
||||
(when
|
||||
(< idx (len queue))
|
||||
(let ((item (nth queue idx)))
|
||||
(do
|
||||
(set! idx (+ idx 1))
|
||||
(let
|
||||
((rel (get item :rel)) (adn (get item :adn)))
|
||||
(for-each
|
||||
(fn
|
||||
(rule)
|
||||
(when
|
||||
(= (dl-rel-name (get rule :head)) rel)
|
||||
(dl-mq-rewrite-rule! rule adn)))
|
||||
rules))
|
||||
(dl-mq-process))))))
|
||||
(dl-mq-process))
|
||||
|
||||
{:rules out
|
||||
:seed
|
||||
(dl-magic-lit
|
||||
query-rel
|
||||
query-adornment
|
||||
query-args)}))))
|
||||
|
||||
;; ── Top-level magic-sets driver ─────────────────────────────────
|
||||
;;
|
||||
;; (dl-magic-query db query-goal) — run `query-goal` under magic-sets
|
||||
;; evaluation. Builds a fresh internal db with:
|
||||
;; - the caller's EDB facts (relations not headed by any rule),
|
||||
;; - the magic seed fact, and
|
||||
;; - the rewritten rules.
|
||||
;; Saturates and queries, returning the substitution list. The
|
||||
;; caller's db is untouched.
|
||||
;;
|
||||
;; Useful primarily as a perf alternative for queries that only
|
||||
;; need a small slice of a recursive relation. Equivalent to
|
||||
;; dl-query for any single fully-stratifiable program.
|
||||
|
||||
(define
|
||||
dl-magic-rule-heads
|
||||
(fn
|
||||
(rules)
|
||||
(let ((seen (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(r)
|
||||
(let ((h (dl-rel-name (get r :head))))
|
||||
(when
|
||||
(and (not (nil? h)) (not (dl-member-string? h seen)))
|
||||
(append! seen h))))
|
||||
rules)
|
||||
seen))))
|
||||
|
||||
;; True iff any rule's body contains a literal kind that the magic
|
||||
;; rewriter doesn't propagate magic to — i.e. an aggregate or a
|
||||
;; negation. Used by dl-magic-query to decide whether to pre-saturate
|
||||
;; the source db (for correctness on stratified programs) or skip
|
||||
;; that step (preserving full magic-sets efficiency for pure
|
||||
;; positive programs).
|
||||
(define
|
||||
dl-rule-has-nonprop-lit?
|
||||
(fn
|
||||
(body i n)
|
||||
(cond
|
||||
((>= i n) false)
|
||||
((let ((lit (nth body i)))
|
||||
(or (and (dict? lit) (has-key? lit :neg))
|
||||
(dl-aggregate? lit)))
|
||||
true)
|
||||
(else (dl-rule-has-nonprop-lit? body (+ i 1) n)))))
|
||||
|
||||
(define
|
||||
dl-rules-need-presaturation?
|
||||
(fn
|
||||
(rules)
|
||||
(cond
|
||||
((= (len rules) 0) false)
|
||||
((let ((body (get (first rules) :body)))
|
||||
(dl-rule-has-nonprop-lit? body 0 (len body)))
|
||||
true)
|
||||
(else (dl-rules-need-presaturation? (rest rules))))))
|
||||
|
||||
(define
|
||||
dl-magic-query
|
||||
(fn
|
||||
(db query-goal)
|
||||
;; Magic-sets only applies to positive non-builtin / non-aggregate
|
||||
;; literals against rule-defined relations. For other goal shapes
|
||||
;; (built-ins, aggregates, EDB-only relations) the seed is either
|
||||
;; non-ground or unused; fall back to dl-query.
|
||||
(cond
|
||||
((not (and (list? query-goal)
|
||||
(> (len query-goal) 0)
|
||||
(symbol? (first query-goal))))
|
||||
(error (str "dl-magic-query: goal must be a positive literal "
|
||||
"(non-empty list with a symbol head), got " query-goal)))
|
||||
((or (dl-builtin? query-goal)
|
||||
(dl-aggregate? query-goal)
|
||||
(and (dict? query-goal) (has-key? query-goal :neg)))
|
||||
(dl-query db query-goal))
|
||||
(else
|
||||
(do
|
||||
;; If the rule set has aggregates or negation, pre-saturate
|
||||
;; the source db before copying facts. The magic rewriter
|
||||
;; passes aggregate body lits and negated lits through
|
||||
;; unchanged (no magic propagation generated for them) — so
|
||||
;; if their inner-goal relation is IDB, it would be empty in
|
||||
;; the magic db. Pre-saturating ensures equivalence with
|
||||
;; `dl-query` for every stratified program. Pure positive
|
||||
;; programs skip this and keep the full magic-sets perf win
|
||||
;; from goal-directed re-derivation.
|
||||
(when
|
||||
(dl-rules-need-presaturation? (dl-rules db))
|
||||
(dl-saturate! db))
|
||||
(let
|
||||
((query-rel (dl-rel-name query-goal))
|
||||
(query-adn (dl-adorn-goal query-goal)))
|
||||
(let
|
||||
((query-args (dl-bound-args query-goal query-adn))
|
||||
(rules (dl-rules db)))
|
||||
(let
|
||||
((rewritten (dl-magic-rewrite rules query-rel query-adn query-args))
|
||||
(mdb (dl-make-db))
|
||||
(rule-heads (dl-magic-rule-heads rules)))
|
||||
(do
|
||||
;; Copy ALL existing facts. EDB-only relations bring their
|
||||
;; tuples; mixed EDB+IDB relations bring both their EDB
|
||||
;; portion and any pre-saturated IDB tuples (which the
|
||||
;; rewritten rules would re-derive anyway). Skipping facts
|
||||
;; for rule-headed relations would leave the magic run
|
||||
;; without the EDB portion of mixed relations.
|
||||
(for-each
|
||||
(fn
|
||||
(rel)
|
||||
(for-each
|
||||
(fn (t) (dl-add-fact! mdb t))
|
||||
(dl-rel-tuples db rel)))
|
||||
(keys (get db :facts)))
|
||||
;; Seed + rewritten rules.
|
||||
(dl-add-fact! mdb (get rewritten :seed))
|
||||
(for-each (fn (r) (dl-add-rule! mdb r)) (get rewritten :rules))
|
||||
(dl-query mdb query-goal))))))))))
|
||||
252
lib/datalog/parser.sx
Normal file
252
lib/datalog/parser.sx
Normal file
@@ -0,0 +1,252 @@
|
||||
;; lib/datalog/parser.sx — Datalog tokens → AST
|
||||
;;
|
||||
;; Output shapes:
|
||||
;; Literal (positive) := (relname arg ... arg) — SX list
|
||||
;; Literal (negative) := {:neg (relname arg ... arg)} — dict
|
||||
;; Argument := var-symbol | atom-symbol | number | string
|
||||
;; | (op-name arg ... arg) — arithmetic compound
|
||||
;; Fact := {:head literal :body ()}
|
||||
;; Rule := {:head literal :body (lit ... lit)}
|
||||
;; Query := {:query (lit ... lit)}
|
||||
;; Program := list of facts / rules / queries
|
||||
;;
|
||||
;; Variables and constants are both SX symbols; the evaluator dispatches
|
||||
;; on first-char case ('A'..'Z' or '_' = variable, otherwise constant).
|
||||
;;
|
||||
;; The parser permits nested compounds in arg position to support
|
||||
;; arithmetic (e.g. (is Z (+ X Y))). Safety analysis at rule-load time
|
||||
;; rejects compounds whose head is not an arithmetic operator.
|
||||
|
||||
(define
|
||||
dl-pp-peek
|
||||
(fn
|
||||
(st)
|
||||
(let
|
||||
((i (get st :idx)) (tokens (get st :tokens)))
|
||||
(if (< i (len tokens)) (nth tokens i) {:type "eof" :value nil :pos 0}))))
|
||||
|
||||
(define
|
||||
dl-pp-peek2
|
||||
(fn
|
||||
(st)
|
||||
(let
|
||||
((i (+ (get st :idx) 1)) (tokens (get st :tokens)))
|
||||
(if (< i (len tokens)) (nth tokens i) {:type "eof" :value nil :pos 0}))))
|
||||
|
||||
(define
|
||||
dl-pp-advance!
|
||||
(fn (st) (dict-set! st :idx (+ (get st :idx) 1))))
|
||||
|
||||
(define
|
||||
dl-pp-at?
|
||||
(fn
|
||||
(st type value)
|
||||
(let
|
||||
((t (dl-pp-peek st)))
|
||||
(and
|
||||
(= (get t :type) type)
|
||||
(or (= value nil) (= (get t :value) value))))))
|
||||
|
||||
(define
|
||||
dl-pp-error
|
||||
(fn
|
||||
(st msg)
|
||||
(let
|
||||
((t (dl-pp-peek st)))
|
||||
(error
|
||||
(str
|
||||
"Parse error at pos "
|
||||
(get t :pos)
|
||||
": "
|
||||
msg
|
||||
" (got "
|
||||
(get t :type)
|
||||
" '"
|
||||
(if (= (get t :value) nil) "" (get t :value))
|
||||
"')")))))
|
||||
|
||||
(define
|
||||
dl-pp-expect!
|
||||
(fn
|
||||
(st type value)
|
||||
(let
|
||||
((t (dl-pp-peek st)))
|
||||
(if
|
||||
(dl-pp-at? st type value)
|
||||
(do (dl-pp-advance! st) t)
|
||||
(dl-pp-error
|
||||
st
|
||||
(str "expected " type (if (= value nil) "" (str " '" value "'"))))))))
|
||||
|
||||
;; Argument: variable, atom, number, string, or compound (relname/op + parens).
|
||||
(define
|
||||
dl-pp-parse-arg
|
||||
(fn
|
||||
(st)
|
||||
(let
|
||||
((t (dl-pp-peek st)))
|
||||
(let
|
||||
((ty (get t :type)) (vv (get t :value)))
|
||||
(cond
|
||||
((= ty "number") (do (dl-pp-advance! st) vv))
|
||||
((= ty "string") (do (dl-pp-advance! st) vv))
|
||||
((= ty "var") (do (dl-pp-advance! st) (string->symbol vv)))
|
||||
;; Negative numeric literal: `-` op directly followed by a
|
||||
;; number (no `(`) is parsed as a single negative number.
|
||||
;; This keeps `(-X Y)` (compound) and `-N` (literal) distinct.
|
||||
((and (= ty "op") (= vv "-")
|
||||
(= (get (dl-pp-peek2 st) :type) "number"))
|
||||
(do
|
||||
(dl-pp-advance! st)
|
||||
(let
|
||||
((n (get (dl-pp-peek st) :value)))
|
||||
(do (dl-pp-advance! st) (- 0 n)))))
|
||||
((or (= ty "atom") (= ty "op"))
|
||||
(do
|
||||
(dl-pp-advance! st)
|
||||
(if
|
||||
(dl-pp-at? st "punct" "(")
|
||||
(do
|
||||
(dl-pp-advance! st)
|
||||
(let
|
||||
((args (dl-pp-parse-arg-list st)))
|
||||
(do
|
||||
(dl-pp-expect! st "punct" ")")
|
||||
(cons (string->symbol vv) args))))
|
||||
(string->symbol vv))))
|
||||
(else (dl-pp-error st "expected term")))))))
|
||||
|
||||
;; Comma-separated args inside parens.
|
||||
(define
|
||||
dl-pp-parse-arg-list
|
||||
(fn
|
||||
(st)
|
||||
(let
|
||||
((args (list)))
|
||||
(do
|
||||
(append! args (dl-pp-parse-arg st))
|
||||
(define
|
||||
dl-pp-arg-loop
|
||||
(fn
|
||||
()
|
||||
(when
|
||||
(dl-pp-at? st "punct" ",")
|
||||
(do
|
||||
(dl-pp-advance! st)
|
||||
(append! args (dl-pp-parse-arg st))
|
||||
(dl-pp-arg-loop)))))
|
||||
(dl-pp-arg-loop)
|
||||
args))))
|
||||
|
||||
;; A positive literal: relname (atom or op) followed by optional (args).
|
||||
(define
|
||||
dl-pp-parse-positive
|
||||
(fn
|
||||
(st)
|
||||
(let
|
||||
((t (dl-pp-peek st)))
|
||||
(let
|
||||
((ty (get t :type)) (vv (get t :value)))
|
||||
(if
|
||||
(or (= ty "atom") (= ty "op"))
|
||||
(do
|
||||
(dl-pp-advance! st)
|
||||
(if
|
||||
(dl-pp-at? st "punct" "(")
|
||||
(do
|
||||
(dl-pp-advance! st)
|
||||
(let
|
||||
((args (dl-pp-parse-arg-list st)))
|
||||
(do
|
||||
(dl-pp-expect! st "punct" ")")
|
||||
(cons (string->symbol vv) args))))
|
||||
(list (string->symbol vv))))
|
||||
(dl-pp-error st "expected literal head"))))))
|
||||
|
||||
;; A body literal: positive, or not(positive).
|
||||
(define
|
||||
dl-pp-parse-body-lit
|
||||
(fn
|
||||
(st)
|
||||
(let
|
||||
((t1 (dl-pp-peek st)) (t2 (dl-pp-peek2 st)))
|
||||
(if
|
||||
(and
|
||||
(= (get t1 :type) "atom")
|
||||
(= (get t1 :value) "not")
|
||||
(= (get t2 :type) "punct")
|
||||
(= (get t2 :value) "("))
|
||||
(do
|
||||
(dl-pp-advance! st)
|
||||
(dl-pp-advance! st)
|
||||
(let
|
||||
((inner (dl-pp-parse-positive st)))
|
||||
(do (dl-pp-expect! st "punct" ")") {:neg inner})))
|
||||
(dl-pp-parse-positive st)))))
|
||||
|
||||
;; Comma-separated body literals.
|
||||
(define
|
||||
dl-pp-parse-body
|
||||
(fn
|
||||
(st)
|
||||
(let
|
||||
((lits (list)))
|
||||
(do
|
||||
(append! lits (dl-pp-parse-body-lit st))
|
||||
(define
|
||||
dl-pp-body-loop
|
||||
(fn
|
||||
()
|
||||
(when
|
||||
(dl-pp-at? st "punct" ",")
|
||||
(do
|
||||
(dl-pp-advance! st)
|
||||
(append! lits (dl-pp-parse-body-lit st))
|
||||
(dl-pp-body-loop)))))
|
||||
(dl-pp-body-loop)
|
||||
lits))))
|
||||
|
||||
;; Single clause: fact, rule, or query. Consumes trailing dot.
|
||||
(define
|
||||
dl-pp-parse-clause
|
||||
(fn
|
||||
(st)
|
||||
(cond
|
||||
((dl-pp-at? st "op" "?-")
|
||||
(do
|
||||
(dl-pp-advance! st)
|
||||
(let
|
||||
((body (dl-pp-parse-body st)))
|
||||
(do (dl-pp-expect! st "punct" ".") {:query body}))))
|
||||
(else
|
||||
(let
|
||||
((head (dl-pp-parse-positive st)))
|
||||
(cond
|
||||
((dl-pp-at? st "op" ":-")
|
||||
(do
|
||||
(dl-pp-advance! st)
|
||||
(let
|
||||
((body (dl-pp-parse-body st)))
|
||||
(do (dl-pp-expect! st "punct" ".") {:body body :head head}))))
|
||||
(else (do (dl-pp-expect! st "punct" ".") {:body (list) :head head}))))))))
|
||||
|
||||
(define
|
||||
dl-parse-program
|
||||
(fn
|
||||
(tokens)
|
||||
(let
|
||||
((st {:tokens tokens :idx 0}) (clauses (list)))
|
||||
(do
|
||||
(define
|
||||
dl-pp-prog-loop
|
||||
(fn
|
||||
()
|
||||
(when
|
||||
(not (dl-pp-at? st "eof" nil))
|
||||
(do
|
||||
(append! clauses (dl-pp-parse-clause st))
|
||||
(dl-pp-prog-loop)))))
|
||||
(dl-pp-prog-loop)
|
||||
clauses))))
|
||||
|
||||
(define dl-parse (fn (src) (dl-parse-program (dl-tokenize src))))
|
||||
20
lib/datalog/scoreboard.json
Normal file
20
lib/datalog/scoreboard.json
Normal file
@@ -0,0 +1,20 @@
|
||||
{
|
||||
"lang": "datalog",
|
||||
"total_passed": 276,
|
||||
"total_failed": 0,
|
||||
"total": 276,
|
||||
"suites": [
|
||||
{"name":"tokenize","passed":31,"failed":0,"total":31},
|
||||
{"name":"parse","passed":23,"failed":0,"total":23},
|
||||
{"name":"unify","passed":29,"failed":0,"total":29},
|
||||
{"name":"eval","passed":44,"failed":0,"total":44},
|
||||
{"name":"builtins","passed":26,"failed":0,"total":26},
|
||||
{"name":"semi_naive","passed":8,"failed":0,"total":8},
|
||||
{"name":"negation","passed":12,"failed":0,"total":12},
|
||||
{"name":"aggregates","passed":23,"failed":0,"total":23},
|
||||
{"name":"api","passed":22,"failed":0,"total":22},
|
||||
{"name":"magic","passed":37,"failed":0,"total":37},
|
||||
{"name":"demo","passed":21,"failed":0,"total":21}
|
||||
],
|
||||
"generated": "2026-05-11T09:40:12+00:00"
|
||||
}
|
||||
17
lib/datalog/scoreboard.md
Normal file
17
lib/datalog/scoreboard.md
Normal file
@@ -0,0 +1,17 @@
|
||||
# datalog scoreboard
|
||||
|
||||
**276 / 276 passing** (0 failure(s)).
|
||||
|
||||
| Suite | Passed | Total | Status |
|
||||
|-------|--------|-------|--------|
|
||||
| tokenize | 31 | 31 | ok |
|
||||
| parse | 23 | 23 | ok |
|
||||
| unify | 29 | 29 | ok |
|
||||
| eval | 44 | 44 | ok |
|
||||
| builtins | 26 | 26 | ok |
|
||||
| semi_naive | 8 | 8 | ok |
|
||||
| negation | 12 | 12 | ok |
|
||||
| aggregates | 23 | 23 | ok |
|
||||
| api | 22 | 22 | ok |
|
||||
| magic | 37 | 37 | ok |
|
||||
| demo | 21 | 21 | ok |
|
||||
323
lib/datalog/strata.sx
Normal file
323
lib/datalog/strata.sx
Normal file
@@ -0,0 +1,323 @@
|
||||
;; lib/datalog/strata.sx — dependency graph, SCC analysis, stratum assignment.
|
||||
;;
|
||||
;; A program is stratifiable iff no cycle in its dependency graph passes
|
||||
;; through a negative edge. The stratum of relation R is the depth at which
|
||||
;; R can first be evaluated:
|
||||
;;
|
||||
;; stratum(R) = max over edges (R → S) of:
|
||||
;; stratum(S) if the edge is positive
|
||||
;; stratum(S) + 1 if the edge is negative
|
||||
;;
|
||||
;; All relations in the same SCC share a stratum (and the SCC must have only
|
||||
;; positive internal edges, else the program is non-stratifiable).
|
||||
|
||||
;; Build dep graph: dict {head-rel-name -> ({:rel str :neg bool} ...)}.
|
||||
(define
|
||||
dl-build-dep-graph
|
||||
(fn
|
||||
(db)
|
||||
(let ((g {}))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(rule)
|
||||
(let
|
||||
((head-rel (dl-rel-name (get rule :head))))
|
||||
(when
|
||||
(not (nil? head-rel))
|
||||
(do
|
||||
(when
|
||||
(not (has-key? g head-rel))
|
||||
(dict-set! g head-rel (list)))
|
||||
(let ((existing (get g head-rel)))
|
||||
(for-each
|
||||
(fn
|
||||
(lit)
|
||||
(cond
|
||||
((dl-aggregate? lit)
|
||||
(let
|
||||
((edge (dl-aggregate-dep-edge lit)))
|
||||
(when
|
||||
(not (nil? edge))
|
||||
(append! existing edge))))
|
||||
(else
|
||||
(let
|
||||
((target
|
||||
(cond
|
||||
((and (dict? lit) (has-key? lit :neg))
|
||||
(dl-rel-name (get lit :neg)))
|
||||
((dl-builtin? lit) nil)
|
||||
((and (list? lit) (> (len lit) 0))
|
||||
(dl-rel-name lit))
|
||||
(else nil)))
|
||||
(neg?
|
||||
(and (dict? lit) (has-key? lit :neg))))
|
||||
(when
|
||||
(not (nil? target))
|
||||
(append!
|
||||
existing
|
||||
{:rel target :neg neg?}))))))
|
||||
(get rule :body)))))))
|
||||
(dl-rules db))
|
||||
g))))
|
||||
|
||||
;; All relations referenced — heads of rules + EDB names + body relations.
|
||||
(define
|
||||
dl-all-relations
|
||||
(fn
|
||||
(db)
|
||||
(let ((seen (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(k)
|
||||
(when (not (dl-member-string? k seen)) (append! seen k)))
|
||||
(keys (get db :facts)))
|
||||
(for-each
|
||||
(fn
|
||||
(rule)
|
||||
(do
|
||||
(let ((h (dl-rel-name (get rule :head))))
|
||||
(when
|
||||
(and (not (nil? h)) (not (dl-member-string? h seen)))
|
||||
(append! seen h)))
|
||||
(for-each
|
||||
(fn
|
||||
(lit)
|
||||
(let
|
||||
((t
|
||||
(cond
|
||||
((dl-aggregate? lit)
|
||||
(let ((edge (dl-aggregate-dep-edge lit)))
|
||||
(if (nil? edge) nil (get edge :rel))))
|
||||
((and (dict? lit) (has-key? lit :neg))
|
||||
(dl-rel-name (get lit :neg)))
|
||||
((dl-builtin? lit) nil)
|
||||
((and (list? lit) (> (len lit) 0))
|
||||
(dl-rel-name lit))
|
||||
(else nil))))
|
||||
(when
|
||||
(and (not (nil? t)) (not (dl-member-string? t seen)))
|
||||
(append! seen t))))
|
||||
(get rule :body))))
|
||||
(dl-rules db))
|
||||
seen))))
|
||||
|
||||
;; reach: dict {from: dict {to: edge-info}} where edge-info is
|
||||
;; {:any bool :neg bool}
|
||||
;; meaning "any path from `from` to `to`" and "exists a negative-passing
|
||||
;; path from `from` to `to`".
|
||||
;;
|
||||
;; Floyd-Warshall over the dep graph. The 'neg' flag propagates through
|
||||
;; concatenation: if any edge along the path is negative, the path's
|
||||
;; flag is true.
|
||||
(define
|
||||
dl-build-reach
|
||||
(fn
|
||||
(graph nodes)
|
||||
(let ((reach {}))
|
||||
(do
|
||||
(for-each
|
||||
(fn (n) (dict-set! reach n {}))
|
||||
nodes)
|
||||
(for-each
|
||||
(fn
|
||||
(head)
|
||||
(when
|
||||
(has-key? graph head)
|
||||
(for-each
|
||||
(fn
|
||||
(edge)
|
||||
(let
|
||||
((target (get edge :rel)) (n (get edge :neg)))
|
||||
(let ((row (get reach head)))
|
||||
(cond
|
||||
((has-key? row target)
|
||||
(let ((cur (get row target)))
|
||||
(dict-set!
|
||||
row
|
||||
target
|
||||
{:any true :neg (or n (get cur :neg))})))
|
||||
(else
|
||||
(dict-set! row target {:any true :neg n}))))))
|
||||
(get graph head))))
|
||||
nodes)
|
||||
(for-each
|
||||
(fn
|
||||
(k)
|
||||
(for-each
|
||||
(fn
|
||||
(i)
|
||||
(let ((row-i (get reach i)))
|
||||
(when
|
||||
(has-key? row-i k)
|
||||
(let ((ik (get row-i k)) (row-k (get reach k)))
|
||||
(for-each
|
||||
(fn
|
||||
(j)
|
||||
(when
|
||||
(has-key? row-k j)
|
||||
(let ((kj (get row-k j)))
|
||||
(let
|
||||
((combined-neg (or (get ik :neg) (get kj :neg))))
|
||||
(cond
|
||||
((has-key? row-i j)
|
||||
(let ((cur (get row-i j)))
|
||||
(dict-set!
|
||||
row-i
|
||||
j
|
||||
{:any true
|
||||
:neg (or combined-neg (get cur :neg))})))
|
||||
(else
|
||||
(dict-set!
|
||||
row-i
|
||||
j
|
||||
{:any true :neg combined-neg})))))))
|
||||
nodes)))))
|
||||
nodes))
|
||||
nodes)
|
||||
reach))))
|
||||
|
||||
;; Returns nil on success, or error message string on failure.
|
||||
(define
|
||||
dl-check-stratifiable
|
||||
(fn
|
||||
(db)
|
||||
(let
|
||||
((graph (dl-build-dep-graph db))
|
||||
(nodes (dl-all-relations db)))
|
||||
(let ((reach (dl-build-reach graph nodes)) (err nil))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(rule)
|
||||
(when
|
||||
(nil? err)
|
||||
(let ((head-rel (dl-rel-name (get rule :head))))
|
||||
(for-each
|
||||
(fn
|
||||
(lit)
|
||||
(cond
|
||||
((and (dict? lit) (has-key? lit :neg))
|
||||
(let ((tgt (dl-rel-name (get lit :neg))))
|
||||
(when
|
||||
(and (not (nil? tgt))
|
||||
(dl-reach-cycle? reach head-rel tgt))
|
||||
(set!
|
||||
err
|
||||
(str "non-stratifiable: relation " head-rel
|
||||
" transitively depends through negation on "
|
||||
tgt
|
||||
" which depends back on " head-rel)))))
|
||||
((dl-aggregate? lit)
|
||||
(let ((edge (dl-aggregate-dep-edge lit)))
|
||||
(when
|
||||
(not (nil? edge))
|
||||
(let ((tgt (get edge :rel)))
|
||||
(when
|
||||
(and (not (nil? tgt))
|
||||
(dl-reach-cycle? reach head-rel tgt))
|
||||
(set!
|
||||
err
|
||||
(str "non-stratifiable: relation "
|
||||
head-rel
|
||||
" aggregates over " tgt
|
||||
" which depends back on "
|
||||
head-rel)))))))))
|
||||
(get rule :body)))))
|
||||
(dl-rules db))
|
||||
err)))))
|
||||
|
||||
(define
|
||||
dl-reach-cycle?
|
||||
(fn
|
||||
(reach a b)
|
||||
(and
|
||||
(dl-reach-row-has? reach b a)
|
||||
(dl-reach-row-has? reach a b))))
|
||||
|
||||
(define
|
||||
dl-reach-row-has?
|
||||
(fn
|
||||
(reach from to)
|
||||
(let ((row (get reach from)))
|
||||
(and (not (nil? row)) (has-key? row to)))))
|
||||
|
||||
;; Compute stratum per relation. Iteratively propagate from EDB roots.
|
||||
;; Uses the per-relation max-stratum-of-deps formula. Stops when stable.
|
||||
(define
|
||||
dl-compute-strata
|
||||
(fn
|
||||
(db)
|
||||
(let
|
||||
((graph (dl-build-dep-graph db))
|
||||
(nodes (dl-all-relations db))
|
||||
(strata {}))
|
||||
(do
|
||||
(for-each (fn (n) (dict-set! strata n 0)) nodes)
|
||||
(let ((changed true))
|
||||
(do
|
||||
(define
|
||||
dl-cs-loop
|
||||
(fn
|
||||
()
|
||||
(when
|
||||
changed
|
||||
(do
|
||||
(set! changed false)
|
||||
(for-each
|
||||
(fn
|
||||
(head)
|
||||
(when
|
||||
(has-key? graph head)
|
||||
(for-each
|
||||
(fn
|
||||
(edge)
|
||||
(let
|
||||
((tgt (get edge :rel))
|
||||
(n (get edge :neg)))
|
||||
(let
|
||||
((tgt-strat
|
||||
(if (has-key? strata tgt)
|
||||
(get strata tgt) 0))
|
||||
(cur (get strata head)))
|
||||
(let
|
||||
((needed
|
||||
(if n (+ tgt-strat 1) tgt-strat)))
|
||||
(when
|
||||
(> needed cur)
|
||||
(do
|
||||
(dict-set! strata head needed)
|
||||
(set! changed true)))))))
|
||||
(get graph head))))
|
||||
nodes)
|
||||
(dl-cs-loop)))))
|
||||
(dl-cs-loop)))
|
||||
strata))))
|
||||
|
||||
;; Group rules by their head's stratum. Returns dict {stratum-int -> rules}.
|
||||
(define
|
||||
dl-group-rules-by-stratum
|
||||
(fn
|
||||
(db strata)
|
||||
(let ((groups {}) (max-s 0))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(rule)
|
||||
(let
|
||||
((head-rel (dl-rel-name (get rule :head))))
|
||||
(let
|
||||
((s (if (has-key? strata head-rel)
|
||||
(get strata head-rel) 0)))
|
||||
(do
|
||||
(when (> s max-s) (set! max-s s))
|
||||
(let
|
||||
((sk (str s)))
|
||||
(do
|
||||
(when
|
||||
(not (has-key? groups sk))
|
||||
(dict-set! groups sk (list)))
|
||||
(append! (get groups sk) rule)))))))
|
||||
(dl-rules db))
|
||||
{:groups groups :max max-s}))))
|
||||
357
lib/datalog/tests/aggregates.sx
Normal file
357
lib/datalog/tests/aggregates.sx
Normal file
@@ -0,0 +1,357 @@
|
||||
;; lib/datalog/tests/aggregates.sx — count / sum / min / max.
|
||||
|
||||
(define dl-at-pass 0)
|
||||
(define dl-at-fail 0)
|
||||
(define dl-at-failures (list))
|
||||
|
||||
(define
|
||||
dl-at-deep=?
|
||||
(fn
|
||||
(a b)
|
||||
(cond
|
||||
((and (list? a) (list? b))
|
||||
(and (= (len a) (len b)) (dl-at-deq-l? a b 0)))
|
||||
((and (dict? a) (dict? b))
|
||||
(let ((ka (keys a)) (kb (keys b)))
|
||||
(and (= (len ka) (len kb)) (dl-at-deq-d? a b ka 0))))
|
||||
((and (number? a) (number? b)) (= a b))
|
||||
(else (equal? a b)))))
|
||||
|
||||
(define
|
||||
dl-at-deq-l?
|
||||
(fn
|
||||
(a b i)
|
||||
(cond
|
||||
((>= i (len a)) true)
|
||||
((not (dl-at-deep=? (nth a i) (nth b i))) false)
|
||||
(else (dl-at-deq-l? a b (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-at-deq-d?
|
||||
(fn
|
||||
(a b ka i)
|
||||
(cond
|
||||
((>= i (len ka)) true)
|
||||
((let ((k (nth ka i)))
|
||||
(not (dl-at-deep=? (get a k) (get b k))))
|
||||
false)
|
||||
(else (dl-at-deq-d? a b ka (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-at-set=?
|
||||
(fn
|
||||
(a b)
|
||||
(and
|
||||
(= (len a) (len b))
|
||||
(dl-at-subset? a b)
|
||||
(dl-at-subset? b a))))
|
||||
|
||||
(define
|
||||
dl-at-subset?
|
||||
(fn
|
||||
(xs ys)
|
||||
(cond
|
||||
((= (len xs) 0) true)
|
||||
((not (dl-at-contains? ys (first xs))) false)
|
||||
(else (dl-at-subset? (rest xs) ys)))))
|
||||
|
||||
(define
|
||||
dl-at-contains?
|
||||
(fn
|
||||
(xs target)
|
||||
(cond
|
||||
((= (len xs) 0) false)
|
||||
((dl-at-deep=? (first xs) target) true)
|
||||
(else (dl-at-contains? (rest xs) target)))))
|
||||
|
||||
(define
|
||||
dl-at-test!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-at-deep=? got expected)
|
||||
(set! dl-at-pass (+ dl-at-pass 1))
|
||||
(do
|
||||
(set! dl-at-fail (+ dl-at-fail 1))
|
||||
(append!
|
||||
dl-at-failures
|
||||
(str
|
||||
name
|
||||
"\n expected: " expected
|
||||
"\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-at-test-set!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-at-set=? got expected)
|
||||
(set! dl-at-pass (+ dl-at-pass 1))
|
||||
(do
|
||||
(set! dl-at-fail (+ dl-at-fail 1))
|
||||
(append!
|
||||
dl-at-failures
|
||||
(str
|
||||
name
|
||||
"\n expected (set): " expected
|
||||
"\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-at-throws?
|
||||
(fn
|
||||
(thunk)
|
||||
(let
|
||||
((threw false))
|
||||
(do
|
||||
(guard
|
||||
(e (#t (set! threw true)))
|
||||
(thunk))
|
||||
threw))))
|
||||
|
||||
(define
|
||||
dl-at-run-all!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
;; count
|
||||
(dl-at-test-set! "count siblings"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"parent(p, bob). parent(p, alice). parent(p, charlie).
|
||||
sibling(X, Y) :- parent(P, X), parent(P, Y), !=(X, Y).
|
||||
sib_count(N) :- count(N, S, sibling(bob, S)).")
|
||||
(list (quote sib_count) (quote N)))
|
||||
(list {:N 2}))
|
||||
|
||||
;; sum
|
||||
(dl-at-test-set! "sum prices"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"price(apple, 5). price(pear, 7). price(plum, 3).
|
||||
total(T) :- sum(T, X, price(F, X)).")
|
||||
(list (quote total) (quote T)))
|
||||
(list {:T 15}))
|
||||
|
||||
;; min
|
||||
(dl-at-test-set! "min score"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"score(alice, 80). score(bob, 65). score(carol, 92).
|
||||
lo(M) :- min(M, S, score(P, S)).")
|
||||
(list (quote lo) (quote M)))
|
||||
(list {:M 65}))
|
||||
|
||||
;; max
|
||||
(dl-at-test-set! "max score"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"score(alice, 80). score(bob, 65). score(carol, 92).
|
||||
hi(M) :- max(M, S, score(P, S)).")
|
||||
(list (quote hi) (quote M)))
|
||||
(list {:M 92}))
|
||||
|
||||
;; count over derived relation (stratification needed).
|
||||
(dl-at-test-set! "count over derived"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"parent(a, b). parent(a, c). parent(b, d). parent(c, e).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).
|
||||
num_ancestors(N) :- count(N, X, ancestor(a, X)).")
|
||||
(list (quote num_ancestors) (quote N)))
|
||||
(list {:N 4}))
|
||||
|
||||
;; count with no matches → 0.
|
||||
(dl-at-test-set! "count empty"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(1). p(2).
|
||||
zero(N) :- count(N, X, q(X)).")
|
||||
(list (quote zero) (quote N)))
|
||||
(list {:N 0}))
|
||||
|
||||
;; sum with no matches → 0.
|
||||
(dl-at-test-set! "sum empty"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(1). p(2).
|
||||
total(T) :- sum(T, X, q(X)).")
|
||||
(list (quote total) (quote T)))
|
||||
(list {:T 0}))
|
||||
|
||||
;; min with no matches → rule does not fire.
|
||||
(dl-at-test-set! "min empty"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(1). p(2).
|
||||
lo(M) :- min(M, X, q(X)).")
|
||||
(list (quote lo) (quote M)))
|
||||
(list))
|
||||
|
||||
;; Aggregate with comparison filter on result.
|
||||
(dl-at-test-set! "popularity threshold"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"post(p1). post(p2).
|
||||
liked(u1, p1). liked(u2, p1). liked(u3, p1).
|
||||
liked(u1, p2). liked(u2, p2).
|
||||
popular(P) :- post(P), count(N, U, liked(U, P)), >=(N, 3).")
|
||||
(list (quote popular) (quote P)))
|
||||
(list {:P (quote p1)}))
|
||||
|
||||
;; findall: collect distinct values into a list.
|
||||
(dl-at-test-set! "findall over EDB"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(a). p(b). p(c).
|
||||
all_p(L) :- findall(L, X, p(X)).")
|
||||
(list (quote all_p) (quote L)))
|
||||
(list {:L (list (quote a) (quote b) (quote c))}))
|
||||
|
||||
(dl-at-test-set! "findall over derived"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"parent(a, b). parent(b, c). parent(c, d).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).
|
||||
desc(L) :- findall(L, X, ancestor(a, X)).")
|
||||
(list (quote desc) (quote L)))
|
||||
(list {:L (list (quote b) (quote c) (quote d))}))
|
||||
|
||||
(dl-at-test-set! "findall empty"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(1).
|
||||
all_q(L) :- findall(L, X, q(X)).")
|
||||
(list (quote all_q) (quote L)))
|
||||
(list {:L (list)}))
|
||||
|
||||
;; Aggregate vs single distinct.
|
||||
;; Group-by via aggregate-in-rule-body. Per-user friend count
|
||||
;; over a friends relation. The U var is bound by the prior
|
||||
;; positive lit u(U) so the aggregate counts only U-rooted
|
||||
;; friends per group.
|
||||
(dl-at-test-set! "group-by per-user friend count"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"u(alice). u(bob). u(carol).
|
||||
f(alice, x). f(alice, y). f(bob, x).
|
||||
counts(U, N) :- u(U), count(N, X, f(U, X)).")
|
||||
(list (quote counts) (quote U) (quote N)))
|
||||
(list
|
||||
{:U (quote alice) :N 2}
|
||||
{:U (quote bob) :N 1}
|
||||
{:U (quote carol) :N 0}))
|
||||
|
||||
;; Stratification: recursion through aggregation is rejected.
|
||||
;; Aggregate validates that second arg is a variable.
|
||||
(dl-at-test! "agg second arg must be var"
|
||||
(dl-at-throws?
|
||||
(fn () (dl-eval "p(1). q(N) :- count(N, 5, p(X))." "?- q(N).")))
|
||||
true)
|
||||
|
||||
;; Aggregate validates that third arg is a positive literal.
|
||||
(dl-at-test! "agg third arg must be a literal"
|
||||
(dl-at-throws?
|
||||
(fn () (dl-eval "p(1). q(N) :- count(N, X, 42)." "?- q(N).")))
|
||||
true)
|
||||
|
||||
;; Aggregate validates that the agg-var (2nd arg) appears in the
|
||||
;; goal. Without it every match contributes the same unbound
|
||||
;; symbol — count silently returns 1, sum raises a confusing
|
||||
;; "expected number" error, etc. Catch the mistake at safety
|
||||
;; check time instead.
|
||||
(dl-at-test! "agg-var must appear in goal"
|
||||
(dl-at-throws?
|
||||
(fn ()
|
||||
(dl-eval
|
||||
"p(1). p(2). c(N) :- count(N, Y, p(X))."
|
||||
"?- c(N).")))
|
||||
true)
|
||||
|
||||
;; Indirect recursion through aggregation also rejected.
|
||||
;; q -> r (via positive lit), r -> q (via aggregate body).
|
||||
;; The aggregate edge counts as negation for stratification.
|
||||
(dl-at-test! "indirect agg cycle rejected"
|
||||
(dl-at-throws?
|
||||
(fn ()
|
||||
(let ((db (dl-make-db)))
|
||||
(do
|
||||
(dl-add-rule! db
|
||||
{:head (list (quote q) (quote N))
|
||||
:body (list (list (quote r) (quote N)))})
|
||||
(dl-add-rule! db
|
||||
{:head (list (quote r) (quote N))
|
||||
:body (list (list (quote count) (quote N) (quote X)
|
||||
(list (quote q) (quote X))))})
|
||||
(dl-saturate! db)))))
|
||||
true)
|
||||
|
||||
(dl-at-test! "agg recursion rejected"
|
||||
(dl-at-throws?
|
||||
(fn ()
|
||||
(let ((db (dl-make-db)))
|
||||
(do
|
||||
(dl-add-rule! db
|
||||
{:head (list (quote q) (quote N))
|
||||
:body (list (list (quote count) (quote N) (quote X)
|
||||
(list (quote q) (quote X))))})
|
||||
(dl-saturate! db)))))
|
||||
true)
|
||||
|
||||
;; Negation + aggregation in the same body — different strata.
|
||||
(dl-at-test-set! "neg + agg coexist"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"u(a). u(b). u(c). banned(b).
|
||||
active(X) :- u(X), not(banned(X)).
|
||||
cnt(N) :- count(N, X, active(X)).")
|
||||
(list (quote cnt) (quote N)))
|
||||
(list {:N 2}))
|
||||
|
||||
;; Min over a derived empty relation: no result.
|
||||
(dl-at-test-set! "min over empty derived"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"s(50). s(60).
|
||||
score(N) :- s(N), >(N, 100).
|
||||
low(M) :- min(M, X, score(X)).")
|
||||
(list (quote low) (quote M)))
|
||||
(list))
|
||||
|
||||
;; Aggregates as the top-level query goal (regression for
|
||||
;; dl-match-lit aggregate dispatch and projection cleanup).
|
||||
(dl-at-test-set! "count as query goal"
|
||||
(dl-query
|
||||
(dl-program "p(1). p(2). p(3). p(4).")
|
||||
(list (quote count) (quote N) (quote X) (list (quote p) (quote X))))
|
||||
(list {:N 4}))
|
||||
|
||||
(dl-at-test-set! "findall as query goal"
|
||||
(dl-query
|
||||
(dl-program "p(1). p(2). p(3).")
|
||||
(list (quote findall) (quote L) (quote X)
|
||||
(list (quote p) (quote X))))
|
||||
(list {:L (list 1 2 3)}))
|
||||
|
||||
(dl-at-test-set! "distinct counted once"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"rated(alice, x). rated(alice, y). rated(bob, x).
|
||||
rater_count(N) :- count(N, U, rated(U, F)).")
|
||||
(list (quote rater_count) (quote N)))
|
||||
(list {:N 2})))))
|
||||
|
||||
(define
|
||||
dl-aggregates-tests-run!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(set! dl-at-pass 0)
|
||||
(set! dl-at-fail 0)
|
||||
(set! dl-at-failures (list))
|
||||
(dl-at-run-all!)
|
||||
{:passed dl-at-pass
|
||||
:failed dl-at-fail
|
||||
:total (+ dl-at-pass dl-at-fail)
|
||||
:failures dl-at-failures})))
|
||||
350
lib/datalog/tests/api.sx
Normal file
350
lib/datalog/tests/api.sx
Normal file
@@ -0,0 +1,350 @@
|
||||
;; lib/datalog/tests/api.sx — SX-data embedding API.
|
||||
|
||||
(define dl-api-pass 0)
|
||||
(define dl-api-fail 0)
|
||||
(define dl-api-failures (list))
|
||||
|
||||
(define
|
||||
dl-api-deep=?
|
||||
(fn
|
||||
(a b)
|
||||
(cond
|
||||
((and (list? a) (list? b))
|
||||
(and (= (len a) (len b)) (dl-api-deq-l? a b 0)))
|
||||
((and (dict? a) (dict? b))
|
||||
(let ((ka (keys a)) (kb (keys b)))
|
||||
(and (= (len ka) (len kb)) (dl-api-deq-d? a b ka 0))))
|
||||
((and (number? a) (number? b)) (= a b))
|
||||
(else (equal? a b)))))
|
||||
|
||||
(define
|
||||
dl-api-deq-l?
|
||||
(fn
|
||||
(a b i)
|
||||
(cond
|
||||
((>= i (len a)) true)
|
||||
((not (dl-api-deep=? (nth a i) (nth b i))) false)
|
||||
(else (dl-api-deq-l? a b (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-api-deq-d?
|
||||
(fn
|
||||
(a b ka i)
|
||||
(cond
|
||||
((>= i (len ka)) true)
|
||||
((let ((k (nth ka i)))
|
||||
(not (dl-api-deep=? (get a k) (get b k))))
|
||||
false)
|
||||
(else (dl-api-deq-d? a b ka (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-api-set=?
|
||||
(fn
|
||||
(a b)
|
||||
(and
|
||||
(= (len a) (len b))
|
||||
(dl-api-subset? a b)
|
||||
(dl-api-subset? b a))))
|
||||
|
||||
(define
|
||||
dl-api-subset?
|
||||
(fn
|
||||
(xs ys)
|
||||
(cond
|
||||
((= (len xs) 0) true)
|
||||
((not (dl-api-contains? ys (first xs))) false)
|
||||
(else (dl-api-subset? (rest xs) ys)))))
|
||||
|
||||
(define
|
||||
dl-api-contains?
|
||||
(fn
|
||||
(xs target)
|
||||
(cond
|
||||
((= (len xs) 0) false)
|
||||
((dl-api-deep=? (first xs) target) true)
|
||||
(else (dl-api-contains? (rest xs) target)))))
|
||||
|
||||
(define
|
||||
dl-api-test!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-api-deep=? got expected)
|
||||
(set! dl-api-pass (+ dl-api-pass 1))
|
||||
(do
|
||||
(set! dl-api-fail (+ dl-api-fail 1))
|
||||
(append!
|
||||
dl-api-failures
|
||||
(str
|
||||
name
|
||||
"\n expected: " expected
|
||||
"\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-api-test-set!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-api-set=? got expected)
|
||||
(set! dl-api-pass (+ dl-api-pass 1))
|
||||
(do
|
||||
(set! dl-api-fail (+ dl-api-fail 1))
|
||||
(append!
|
||||
dl-api-failures
|
||||
(str
|
||||
name
|
||||
"\n expected (set): " expected
|
||||
"\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-api-run-all!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
;; dl-program-data with arrow form.
|
||||
(dl-api-test-set! "data API ancestor closure"
|
||||
(dl-query
|
||||
(dl-program-data
|
||||
(quote ((parent tom bob) (parent bob ann) (parent ann pat)))
|
||||
(quote
|
||||
((ancestor X Y <- (parent X Y))
|
||||
(ancestor X Z <- (parent X Y) (ancestor Y Z)))))
|
||||
(quote (ancestor tom X)))
|
||||
(list {:X (quote bob)} {:X (quote ann)} {:X (quote pat)}))
|
||||
|
||||
;; dl-program-data with dict rules.
|
||||
(dl-api-test-set! "data API with dict rules"
|
||||
(dl-query
|
||||
(dl-program-data
|
||||
(quote ((p a) (p b) (p c)))
|
||||
(list
|
||||
{:head (quote (q X)) :body (quote ((p X)))}))
|
||||
(quote (q X)))
|
||||
(list {:X (quote a)} {:X (quote b)} {:X (quote c)}))
|
||||
|
||||
;; dl-rule helper.
|
||||
(dl-api-test-set! "dl-rule constructor"
|
||||
(dl-query
|
||||
(dl-program-data
|
||||
(quote ((p 1) (p 2)))
|
||||
(list (dl-rule (quote (q X)) (quote ((p X))))))
|
||||
(quote (q X)))
|
||||
(list {:X 1} {:X 2}))
|
||||
|
||||
;; dl-assert! adds and re-derives.
|
||||
(dl-api-test-set! "dl-assert! incremental"
|
||||
(let
|
||||
((db (dl-program-data
|
||||
(quote ((parent tom bob) (parent bob ann)))
|
||||
(quote
|
||||
((ancestor X Y <- (parent X Y))
|
||||
(ancestor X Z <- (parent X Y) (ancestor Y Z)))))))
|
||||
(do
|
||||
(dl-saturate! db)
|
||||
(dl-assert! db (quote (parent ann pat)))
|
||||
(dl-query db (quote (ancestor tom X)))))
|
||||
(list {:X (quote bob)} {:X (quote ann)} {:X (quote pat)}))
|
||||
|
||||
;; dl-retract! removes a fact and recomputes IDB.
|
||||
(dl-api-test-set! "dl-retract! removes derived"
|
||||
(let
|
||||
((db (dl-program-data
|
||||
(quote ((parent tom bob) (parent bob ann) (parent ann pat)))
|
||||
(quote
|
||||
((ancestor X Y <- (parent X Y))
|
||||
(ancestor X Z <- (parent X Y) (ancestor Y Z)))))))
|
||||
(do
|
||||
(dl-saturate! db)
|
||||
(dl-retract! db (quote (parent bob ann)))
|
||||
(dl-query db (quote (ancestor tom X)))))
|
||||
(list {:X (quote bob)}))
|
||||
|
||||
;; dl-retract! on a relation with BOTH explicit facts AND a rule
|
||||
;; (a "mixed" relation) used to wipe the EDB portion when the IDB
|
||||
;; was re-derived, even when the retract didn't match anything.
|
||||
;; :edb-keys provenance now preserves user-asserted facts.
|
||||
(dl-api-test-set! "dl-retract! preserves EDB in mixed relation"
|
||||
(let
|
||||
((db (dl-program-data
|
||||
(quote ((p a) (p b) (q c)))
|
||||
(quote ((p X <- (q X)))))))
|
||||
(do
|
||||
(dl-saturate! db)
|
||||
;; Retract a non-existent tuple — should be a no-op.
|
||||
(dl-retract! db (quote (p z)))
|
||||
(dl-query db (quote (p X)))))
|
||||
(list {:X (quote a)} {:X (quote b)} {:X (quote c)}))
|
||||
|
||||
;; And retracting an actual EDB fact in a mixed relation drops
|
||||
;; only that fact; the derived portion stays.
|
||||
(dl-api-test-set! "dl-retract! mixed: drop EDB, keep IDB"
|
||||
(let
|
||||
((db (dl-program-data
|
||||
(quote ((p a) (p b) (q c)))
|
||||
(quote ((p X <- (q X)))))))
|
||||
(do
|
||||
(dl-saturate! db)
|
||||
(dl-retract! db (quote (p a)))
|
||||
(dl-query db (quote (p X)))))
|
||||
(list {:X (quote b)} {:X (quote c)}))
|
||||
|
||||
;; dl-program-data + dl-query with constants in head.
|
||||
(dl-api-test-set! "constant-in-head data"
|
||||
(dl-query
|
||||
(dl-program-data
|
||||
(quote ((edge a b) (edge b c) (edge c a)))
|
||||
(quote
|
||||
((reach X Y <- (edge X Y))
|
||||
(reach X Z <- (edge X Y) (reach Y Z)))))
|
||||
(quote (reach a X)))
|
||||
(list {:X (quote a)} {:X (quote b)} {:X (quote c)}))
|
||||
|
||||
;; Assert into empty db.
|
||||
(dl-api-test-set! "assert into empty"
|
||||
(let
|
||||
((db (dl-program-data (list) (list))))
|
||||
(do
|
||||
(dl-assert! db (quote (p 1)))
|
||||
(dl-assert! db (quote (p 2)))
|
||||
(dl-query db (quote (p X)))))
|
||||
(list {:X 1} {:X 2}))
|
||||
|
||||
;; Multi-goal query: pass list of literals.
|
||||
(dl-api-test-set! "multi-goal query"
|
||||
(dl-query
|
||||
(dl-program-data
|
||||
(quote ((p 1) (p 2) (p 3) (q 2) (q 3)))
|
||||
(list))
|
||||
(list (quote (p X)) (quote (q X))))
|
||||
(list {:X 2} {:X 3}))
|
||||
|
||||
;; Multi-goal with comparison.
|
||||
(dl-api-test-set! "multi-goal with comparison"
|
||||
(dl-query
|
||||
(dl-program-data
|
||||
(quote ((n 1) (n 2) (n 3) (n 4) (n 5)))
|
||||
(list))
|
||||
(list (quote (n X)) (list (string->symbol ">") (quote X) 2)))
|
||||
(list {:X 3} {:X 4} {:X 5}))
|
||||
|
||||
;; dl-eval: single-call source + query.
|
||||
(dl-api-test-set! "dl-eval ancestor"
|
||||
(dl-eval
|
||||
"parent(a, b). parent(b, c).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z)."
|
||||
"?- ancestor(a, X).")
|
||||
(list {:X (quote b)} {:X (quote c)}))
|
||||
|
||||
(dl-api-test-set! "dl-eval multi-goal"
|
||||
(dl-eval
|
||||
"p(1). p(2). p(3). q(2). q(3)."
|
||||
"?- p(X), q(X).")
|
||||
(list {:X 2} {:X 3}))
|
||||
|
||||
;; dl-rules-of: rules with head matching a relation name.
|
||||
(dl-api-test! "dl-rules-of count"
|
||||
(let
|
||||
((db (dl-program
|
||||
"p(1). q(X) :- p(X). r(X) :- p(X). q(2).")))
|
||||
(len (dl-rules-of db "q")))
|
||||
1)
|
||||
|
||||
(dl-api-test! "dl-rules-of empty"
|
||||
(let
|
||||
((db (dl-program "p(1). p(2).")))
|
||||
(len (dl-rules-of db "q")))
|
||||
0)
|
||||
|
||||
;; dl-clear-idb!: wipe rule-headed relations.
|
||||
(dl-api-test! "dl-clear-idb! wipes IDB"
|
||||
(let
|
||||
((db (dl-program
|
||||
"parent(a, b). parent(b, c).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")))
|
||||
(do
|
||||
(dl-saturate! db)
|
||||
(dl-clear-idb! db)
|
||||
(len (dl-relation db "ancestor"))))
|
||||
0)
|
||||
|
||||
(dl-api-test! "dl-clear-idb! preserves EDB"
|
||||
(let
|
||||
((db (dl-program
|
||||
"parent(a, b). parent(b, c).
|
||||
ancestor(X, Y) :- parent(X, Y).")))
|
||||
(do
|
||||
(dl-saturate! db)
|
||||
(dl-clear-idb! db)
|
||||
(len (dl-relation db "parent"))))
|
||||
2)
|
||||
|
||||
;; dl-eval-magic — routes single-goal queries through
|
||||
;; magic-sets evaluation.
|
||||
(dl-api-test-set! "dl-eval-magic ancestor"
|
||||
(dl-eval-magic
|
||||
"parent(a, b). parent(b, c).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z)."
|
||||
"?- ancestor(a, X).")
|
||||
(list {:X (quote b)} {:X (quote c)}))
|
||||
|
||||
;; Equivalence: dl-eval and dl-eval-magic produce the same
|
||||
;; answers for any well-formed query (magic-sets is a perf
|
||||
;; alternative, not a semantic change).
|
||||
(dl-api-test! "dl-eval ≡ dl-eval-magic on ancestor"
|
||||
(let
|
||||
((source "parent(a, b). parent(b, c). parent(c, d).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z)."))
|
||||
(let
|
||||
((semi (dl-eval source "?- ancestor(a, X)."))
|
||||
(magic (dl-eval-magic source "?- ancestor(a, X).")))
|
||||
(= (len semi) (len magic))))
|
||||
true)
|
||||
|
||||
;; Comprehensive integration: recursion + stratified negation
|
||||
;; + aggregation + comparison composed in a single program.
|
||||
;; (Uses _Anything as a regular var instead of `_` so the
|
||||
;; outer rule binds via the reach lit.)
|
||||
(dl-api-test-set! "integration"
|
||||
(dl-eval
|
||||
(str
|
||||
"edge(a, b). edge(b, c). edge(c, d). edge(a, d). "
|
||||
"banned(c). "
|
||||
"reach(X, Y) :- edge(X, Y). "
|
||||
"reach(X, Z) :- edge(X, Y), reach(Y, Z). "
|
||||
"safe(X, Y) :- reach(X, Y), not(banned(Y)). "
|
||||
"reach_count(X, N) :- reach(X, Z), count(N, Y, safe(X, Y)). "
|
||||
"popular(X) :- reach_count(X, N), >=(N, 2).")
|
||||
"?- popular(X).")
|
||||
(list {:X (quote a)}))
|
||||
|
||||
;; dl-rule-from-list with no arrow → fact-style.
|
||||
(dl-api-test-set! "no arrow → fact-like rule"
|
||||
(let
|
||||
((rule (dl-rule-from-list (quote (foo X Y)))))
|
||||
(list rule))
|
||||
(list {:head (quote (foo X Y)) :body (list)}))
|
||||
|
||||
;; dl-coerce-rule on dict passes through.
|
||||
(dl-api-test-set! "coerce dict rule"
|
||||
(let
|
||||
((d {:head (quote (h X)) :body (quote ((b X)))}))
|
||||
(list (dl-coerce-rule d)))
|
||||
(list {:head (quote (h X)) :body (quote ((b X)))})))))
|
||||
|
||||
(define
|
||||
dl-api-tests-run!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(set! dl-api-pass 0)
|
||||
(set! dl-api-fail 0)
|
||||
(set! dl-api-failures (list))
|
||||
(dl-api-run-all!)
|
||||
{:passed dl-api-pass
|
||||
:failed dl-api-fail
|
||||
:total (+ dl-api-pass dl-api-fail)
|
||||
:failures dl-api-failures})))
|
||||
285
lib/datalog/tests/builtins.sx
Normal file
285
lib/datalog/tests/builtins.sx
Normal file
@@ -0,0 +1,285 @@
|
||||
;; lib/datalog/tests/builtins.sx — comparison + arithmetic body literals.
|
||||
|
||||
(define dl-bt-pass 0)
|
||||
(define dl-bt-fail 0)
|
||||
(define dl-bt-failures (list))
|
||||
|
||||
(define
|
||||
dl-bt-deep=?
|
||||
(fn
|
||||
(a b)
|
||||
(cond
|
||||
((and (list? a) (list? b))
|
||||
(and (= (len a) (len b)) (dl-bt-deq-l? a b 0)))
|
||||
((and (dict? a) (dict? b))
|
||||
(let
|
||||
((ka (keys a)) (kb (keys b)))
|
||||
(and (= (len ka) (len kb)) (dl-bt-deq-d? a b ka 0))))
|
||||
((and (number? a) (number? b)) (= a b))
|
||||
(else (equal? a b)))))
|
||||
|
||||
(define
|
||||
dl-bt-deq-l?
|
||||
(fn
|
||||
(a b i)
|
||||
(cond
|
||||
((>= i (len a)) true)
|
||||
((not (dl-bt-deep=? (nth a i) (nth b i))) false)
|
||||
(else (dl-bt-deq-l? a b (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-bt-deq-d?
|
||||
(fn
|
||||
(a b ka i)
|
||||
(cond
|
||||
((>= i (len ka)) true)
|
||||
((let ((k (nth ka i))) (not (dl-bt-deep=? (get a k) (get b k))))
|
||||
false)
|
||||
(else (dl-bt-deq-d? a b ka (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-bt-set=?
|
||||
(fn
|
||||
(a b)
|
||||
(and (= (len a) (len b)) (dl-bt-subset? a b) (dl-bt-subset? b a))))
|
||||
|
||||
(define
|
||||
dl-bt-subset?
|
||||
(fn
|
||||
(xs ys)
|
||||
(cond
|
||||
((= (len xs) 0) true)
|
||||
((not (dl-bt-contains? ys (first xs))) false)
|
||||
(else (dl-bt-subset? (rest xs) ys)))))
|
||||
|
||||
(define
|
||||
dl-bt-contains?
|
||||
(fn
|
||||
(xs target)
|
||||
(cond
|
||||
((= (len xs) 0) false)
|
||||
((dl-bt-deep=? (first xs) target) true)
|
||||
(else (dl-bt-contains? (rest xs) target)))))
|
||||
|
||||
(define
|
||||
dl-bt-test-set!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-bt-set=? got expected)
|
||||
(set! dl-bt-pass (+ dl-bt-pass 1))
|
||||
(do
|
||||
(set! dl-bt-fail (+ dl-bt-fail 1))
|
||||
(append!
|
||||
dl-bt-failures
|
||||
(str
|
||||
name
|
||||
"\n expected (set): "
|
||||
expected
|
||||
"\n got: "
|
||||
got))))))
|
||||
|
||||
(define
|
||||
dl-bt-test!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-bt-deep=? got expected)
|
||||
(set! dl-bt-pass (+ dl-bt-pass 1))
|
||||
(do
|
||||
(set! dl-bt-fail (+ dl-bt-fail 1))
|
||||
(append!
|
||||
dl-bt-failures
|
||||
(str name "\n expected: " expected "\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-bt-throws?
|
||||
(fn
|
||||
(thunk)
|
||||
(let
|
||||
((threw false))
|
||||
(do (guard (e (#t (set! threw true))) (thunk)) threw))))
|
||||
|
||||
(define
|
||||
dl-bt-run-all!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(dl-bt-test-set!
|
||||
"less than filter"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"age(alice, 30). age(bob, 17). age(carol, 22).\n adult(X) :- age(X, A), >=(A, 18).")
|
||||
(list (quote adult) (quote X)))
|
||||
(list {:X (quote alice)} {:X (quote carol)}))
|
||||
(dl-bt-test-set!
|
||||
"less-equal filter"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"n(1). n(2). n(3). n(4). n(5).\n small(X) :- n(X), <=(X, 3).")
|
||||
(list (quote small) (quote X)))
|
||||
(list {:X 1} {:X 2} {:X 3}))
|
||||
(dl-bt-test-set!
|
||||
"not-equal filter"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(1, 2). p(2, 2). p(3, 4).\n diff(X, Y) :- p(X, Y), !=(X, Y).")
|
||||
(list (quote diff) (quote X) (quote Y)))
|
||||
(list {:X 1 :Y 2} {:X 3 :Y 4}))
|
||||
(dl-bt-test-set!
|
||||
"is plus"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"n(1). n(2). n(3).\n succ(X, Y) :- n(X), is(Y, +(X, 1)).")
|
||||
(list (quote succ) (quote X) (quote Y)))
|
||||
(list {:X 1 :Y 2} {:X 2 :Y 3} {:X 3 :Y 4}))
|
||||
(dl-bt-test-set!
|
||||
"is multiply"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"n(2). n(3). n(4).\n square(X, Y) :- n(X), is(Y, *(X, X)).")
|
||||
(list (quote square) (quote X) (quote Y)))
|
||||
(list {:X 2 :Y 4} {:X 3 :Y 9} {:X 4 :Y 16}))
|
||||
(dl-bt-test-set!
|
||||
"is nested expr"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"n(1). n(2). n(3).\n f(X, Y) :- n(X), is(Y, *(+(X, 1), 2)).")
|
||||
(list (quote f) (quote X) (quote Y)))
|
||||
(list {:X 1 :Y 4} {:X 2 :Y 6} {:X 3 :Y 8}))
|
||||
(dl-bt-test-set!
|
||||
"is bound LHS — equality"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"n(1, 2). n(2, 5). n(3, 4).\n succ(X, Y) :- n(X, Y), is(Y, +(X, 1)).")
|
||||
(list (quote succ) (quote X) (quote Y)))
|
||||
(list {:X 1 :Y 2} {:X 3 :Y 4}))
|
||||
(dl-bt-test-set!
|
||||
"triple via is"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"n(1). n(2). n(3).\n triple(X, Y) :- n(X), is(Y, *(X, 3)).")
|
||||
(list (quote triple) (quote X) (quote Y)))
|
||||
(list {:X 1 :Y 3} {:X 2 :Y 6} {:X 3 :Y 9}))
|
||||
(dl-bt-test-set!
|
||||
"= unifies var with constant"
|
||||
(dl-query
|
||||
(dl-program "p(a). p(b).\n qual(X) :- p(X), =(X, a).")
|
||||
(list (quote qual) (quote X)))
|
||||
(list {:X (quote a)}))
|
||||
(dl-bt-test-set!
|
||||
"= unifies two vars (one bound)"
|
||||
(dl-query
|
||||
(dl-program "p(a). p(b).\n twin(X, Y) :- p(X), =(Y, X).")
|
||||
(list (quote twin) (quote X) (quote Y)))
|
||||
(list {:X (quote a) :Y (quote a)} {:X (quote b) :Y (quote b)}))
|
||||
(dl-bt-test!
|
||||
"big count"
|
||||
(let
|
||||
((db (dl-program "n(0). n(1). n(2). n(3). n(4). n(5). n(6). n(7). n(8). n(9).\n big(X) :- n(X), >=(X, 5).")))
|
||||
(do (dl-saturate! db) (len (dl-relation db "big"))))
|
||||
5)
|
||||
;; Built-in / arithmetic literals work as standalone query goals
|
||||
;; (without needing a wrapper rule).
|
||||
(dl-bt-test-set! "comparison-only goal true"
|
||||
(dl-eval "" "?- <(1, 2).")
|
||||
(list {}))
|
||||
|
||||
(dl-bt-test-set! "comparison-only goal false"
|
||||
(dl-eval "" "?- <(2, 1).")
|
||||
(list))
|
||||
|
||||
(dl-bt-test-set! "is goal binds"
|
||||
(dl-eval "" "?- is(N, +(2, 3)).")
|
||||
(list {:N 5}))
|
||||
|
||||
;; Bounded successor: a recursive rule with a comparison
|
||||
;; guard terminates because the Herbrand base is effectively
|
||||
;; bounded.
|
||||
(dl-bt-test-set! "bounded successor"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"nat(0).
|
||||
nat(Y) :- nat(X), is(Y, +(X, 1)), <(Y, 5).")
|
||||
(list (quote nat) (quote X)))
|
||||
(list {:X 0} {:X 1} {:X 2} {:X 3} {:X 4}))
|
||||
|
||||
(dl-bt-test!
|
||||
"unsafe — comparison without binder"
|
||||
(dl-bt-throws? (fn () (dl-program "p(X) :- <(X, 5).")))
|
||||
true)
|
||||
(dl-bt-test!
|
||||
"unsafe — comparison both unbound"
|
||||
(dl-bt-throws? (fn () (dl-program "p(X, Y) :- <(X, Y), q(X).")))
|
||||
true)
|
||||
(dl-bt-test!
|
||||
"unsafe — is uses unbound RHS var"
|
||||
(dl-bt-throws?
|
||||
(fn () (dl-program "p(X, Y) :- q(X), is(Y, +(X, Z)).")))
|
||||
true)
|
||||
(dl-bt-test!
|
||||
"unsafe — is on its own"
|
||||
(dl-bt-throws? (fn () (dl-program "p(Y) :- is(Y, +(X, 1)).")))
|
||||
true)
|
||||
(dl-bt-test!
|
||||
"unsafe — = between two unbound"
|
||||
(dl-bt-throws? (fn () (dl-program "p(X, Y) :- =(X, Y).")))
|
||||
true)
|
||||
(dl-bt-test!
|
||||
"safe — is binds head var"
|
||||
(dl-bt-throws?
|
||||
(fn () (dl-program "n(1). p(Y) :- n(X), is(Y, +(X, 1)).")))
|
||||
false)
|
||||
(dl-bt-test!
|
||||
"safe — comparison after binder"
|
||||
(dl-bt-throws?
|
||||
(fn () (dl-program "n(1). big(X) :- n(X), >=(X, 0).")))
|
||||
false)
|
||||
(dl-bt-test!
|
||||
"safe — = binds head var"
|
||||
(dl-bt-throws?
|
||||
(fn () (dl-program "p(a). p(b). x(Y) :- p(X), =(Y, X).")))
|
||||
false)
|
||||
|
||||
;; Division by zero raises with a clear error. Without this guard
|
||||
;; SX's `/` returned IEEE infinity, which then silently flowed
|
||||
;; through comparisons and aggregations.
|
||||
(dl-bt-test!
|
||||
"is — division by zero raises"
|
||||
(dl-bt-throws?
|
||||
(fn ()
|
||||
(dl-eval "p(10). q(R) :- p(X), is(R, /(X, 0))." "?- q(R).")))
|
||||
true)
|
||||
|
||||
;; Comparison ops `<`, `<=`, `>`, `>=` require both operands to
|
||||
;; have the same primitive type. Cross-type comparisons used to
|
||||
;; silently return false (for some pairs) or raise a confusing
|
||||
;; host-level error (for others) — now they all raise with a
|
||||
;; message that names the offending values.
|
||||
(dl-bt-test!
|
||||
"comparison — string vs number raises"
|
||||
(dl-bt-throws?
|
||||
(fn ()
|
||||
(dl-eval "p(\"hello\"). q(X) :- p(X), <(X, 5)." "?- q(X).")))
|
||||
true)
|
||||
|
||||
;; `!=` is the exception — it's a polymorphic inequality test
|
||||
;; (uses dl-tuple-equal? underneath) so cross-type pairs are
|
||||
;; legitimate (and trivially unequal).
|
||||
(dl-bt-test-set! "!= works across types"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(1). p(\"1\"). q(X) :- p(X), !=(X, 1).")
|
||||
(quote (q X)))
|
||||
(list {:X "1"})))))
|
||||
|
||||
(define
|
||||
dl-builtins-tests-run!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(set! dl-bt-pass 0)
|
||||
(set! dl-bt-fail 0)
|
||||
(set! dl-bt-failures (list))
|
||||
(dl-bt-run-all!)
|
||||
{:failures dl-bt-failures :total (+ dl-bt-pass dl-bt-fail) :passed dl-bt-pass :failed dl-bt-fail})))
|
||||
321
lib/datalog/tests/demo.sx
Normal file
321
lib/datalog/tests/demo.sx
Normal file
@@ -0,0 +1,321 @@
|
||||
;; lib/datalog/tests/demo.sx — Phase 10 demo programs.
|
||||
|
||||
(define dl-demo-pass 0)
|
||||
(define dl-demo-fail 0)
|
||||
(define dl-demo-failures (list))
|
||||
|
||||
(define
|
||||
dl-demo-deep=?
|
||||
(fn
|
||||
(a b)
|
||||
(cond
|
||||
((and (list? a) (list? b))
|
||||
(and (= (len a) (len b)) (dl-demo-deq-l? a b 0)))
|
||||
((and (dict? a) (dict? b))
|
||||
(let ((ka (keys a)) (kb (keys b)))
|
||||
(and (= (len ka) (len kb)) (dl-demo-deq-d? a b ka 0))))
|
||||
((and (number? a) (number? b)) (= a b))
|
||||
(else (equal? a b)))))
|
||||
|
||||
(define
|
||||
dl-demo-deq-l?
|
||||
(fn
|
||||
(a b i)
|
||||
(cond
|
||||
((>= i (len a)) true)
|
||||
((not (dl-demo-deep=? (nth a i) (nth b i))) false)
|
||||
(else (dl-demo-deq-l? a b (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-demo-deq-d?
|
||||
(fn
|
||||
(a b ka i)
|
||||
(cond
|
||||
((>= i (len ka)) true)
|
||||
((let ((k (nth ka i)))
|
||||
(not (dl-demo-deep=? (get a k) (get b k))))
|
||||
false)
|
||||
(else (dl-demo-deq-d? a b ka (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-demo-set=?
|
||||
(fn
|
||||
(a b)
|
||||
(and
|
||||
(= (len a) (len b))
|
||||
(dl-demo-subset? a b)
|
||||
(dl-demo-subset? b a))))
|
||||
|
||||
(define
|
||||
dl-demo-subset?
|
||||
(fn
|
||||
(xs ys)
|
||||
(cond
|
||||
((= (len xs) 0) true)
|
||||
((not (dl-demo-contains? ys (first xs))) false)
|
||||
(else (dl-demo-subset? (rest xs) ys)))))
|
||||
|
||||
(define
|
||||
dl-demo-contains?
|
||||
(fn
|
||||
(xs target)
|
||||
(cond
|
||||
((= (len xs) 0) false)
|
||||
((dl-demo-deep=? (first xs) target) true)
|
||||
(else (dl-demo-contains? (rest xs) target)))))
|
||||
|
||||
(define
|
||||
dl-demo-test-set!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-demo-set=? got expected)
|
||||
(set! dl-demo-pass (+ dl-demo-pass 1))
|
||||
(do
|
||||
(set! dl-demo-fail (+ dl-demo-fail 1))
|
||||
(append!
|
||||
dl-demo-failures
|
||||
(str
|
||||
name
|
||||
"\n expected (set): " expected
|
||||
"\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-demo-run-all!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
;; ── Federation ──────────────────────────────────────────
|
||||
(dl-demo-test-set! "mutuals"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote ((follows alice bob) (follows bob alice)
|
||||
(follows bob carol) (follows carol dave)))
|
||||
dl-demo-federation-rules)
|
||||
(quote (mutual alice X)))
|
||||
(list {:X (quote bob)}))
|
||||
|
||||
(dl-demo-test-set! "reachable transitive"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote ((follows alice bob) (follows bob carol) (follows carol dave)))
|
||||
dl-demo-federation-rules)
|
||||
(quote (reachable alice X)))
|
||||
(list {:X (quote bob)} {:X (quote carol)} {:X (quote dave)}))
|
||||
|
||||
(dl-demo-test-set! "foaf"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote ((follows alice bob) (follows bob carol) (follows alice dave)))
|
||||
dl-demo-federation-rules)
|
||||
(quote (foaf alice X)))
|
||||
(list {:X (quote carol)}))
|
||||
|
||||
;; ── Content ─────────────────────────────────────────────
|
||||
(dl-demo-test-set! "popular posts"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((authored alice p1) (authored bob p2) (authored carol p3)
|
||||
(liked u1 p1) (liked u2 p1) (liked u3 p1)
|
||||
(liked u1 p2)))
|
||||
dl-demo-content-rules)
|
||||
(quote (popular P)))
|
||||
(list {:P (quote p1)}))
|
||||
|
||||
(dl-demo-test-set! "interesting feed"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((follows me alice) (follows me bob)
|
||||
(authored alice p1) (authored bob p2)
|
||||
(liked u1 p1) (liked u2 p1) (liked u3 p1)
|
||||
(liked u4 p2)))
|
||||
dl-demo-content-rules)
|
||||
(quote (interesting me P)))
|
||||
(list {:P (quote p1)}))
|
||||
|
||||
(dl-demo-test-set! "post likes count"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((authored alice p1)
|
||||
(liked u1 p1) (liked u2 p1) (liked u3 p1)))
|
||||
dl-demo-content-rules)
|
||||
(quote (post-likes p1 N)))
|
||||
(list {:N 3}))
|
||||
|
||||
;; ── Permissions ─────────────────────────────────────────
|
||||
(dl-demo-test-set! "direct group access"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((member alice editors)
|
||||
(allowed editors blog)))
|
||||
dl-demo-perm-rules)
|
||||
(quote (can-access X blog)))
|
||||
(list {:X (quote alice)}))
|
||||
|
||||
(dl-demo-test-set! "subgroup access"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((member bob writers)
|
||||
(subgroup writers editors)
|
||||
(allowed editors blog)))
|
||||
dl-demo-perm-rules)
|
||||
(quote (can-access X blog)))
|
||||
(list {:X (quote bob)}))
|
||||
|
||||
(dl-demo-test-set! "transitive subgroup"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((member carol drafters)
|
||||
(subgroup drafters writers)
|
||||
(subgroup writers editors)
|
||||
(allowed editors blog)))
|
||||
dl-demo-perm-rules)
|
||||
(quote (can-access X blog)))
|
||||
(list {:X (quote carol)}))
|
||||
|
||||
;; ── Cooking posts (canonical Phase 10 example) ─────────
|
||||
(dl-demo-test-set! "cooking posts by network"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((follows me alice) (follows alice bob) (follows alice carol)
|
||||
(authored alice p1) (authored bob p2)
|
||||
(authored carol p3) (authored carol p4)
|
||||
(tagged p1 travel) (tagged p2 cooking)
|
||||
(tagged p3 cooking) (tagged p4 books)))
|
||||
dl-demo-cooking-rules)
|
||||
(quote (cooking-post-by-network me P)))
|
||||
(list {:P (quote p2)} {:P (quote p3)}))
|
||||
|
||||
(dl-demo-test-set! "cooking — direct follow only"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((follows me bob)
|
||||
(authored bob p1) (authored bob p2)
|
||||
(tagged p1 cooking) (tagged p2 books)))
|
||||
dl-demo-cooking-rules)
|
||||
(quote (cooking-post-by-network me P)))
|
||||
(list {:P (quote p1)}))
|
||||
|
||||
(dl-demo-test-set! "cooking — none in network"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((follows me bob)
|
||||
(authored bob p1) (tagged p1 books)))
|
||||
dl-demo-cooking-rules)
|
||||
(quote (cooking-post-by-network me P)))
|
||||
(list))
|
||||
|
||||
;; ── Tag co-occurrence ──────────────────────────────────
|
||||
(dl-demo-test-set! "cotagged posts"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((tagged p1 cooking) (tagged p1 vegetarian)
|
||||
(tagged p2 cooking) (tagged p2 quick)
|
||||
(tagged p3 vegetarian)))
|
||||
dl-demo-tag-cooccur-rules)
|
||||
(quote (cotagged P cooking vegetarian)))
|
||||
(list {:P (quote p1)}))
|
||||
|
||||
(dl-demo-test-set! "tag pair count"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((tagged p1 cooking) (tagged p1 vegetarian)
|
||||
(tagged p2 cooking) (tagged p2 quick)
|
||||
(tagged p3 cooking) (tagged p3 vegetarian)))
|
||||
dl-demo-tag-cooccur-rules)
|
||||
(quote (tag-pair-count cooking vegetarian N)))
|
||||
(list {:N 2}))
|
||||
|
||||
;; ── Shortest path on a weighted DAG ──────────────────
|
||||
(dl-demo-test-set! "shortest a→d via DAG"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote ((edge a b 5) (edge b c 3) (edge a c 10) (edge c d 2)))
|
||||
dl-demo-shortest-path-rules)
|
||||
(quote (shortest a d W)))
|
||||
(list {:W 10}))
|
||||
|
||||
(dl-demo-test-set! "shortest a→c picks 2-hop"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote ((edge a b 5) (edge b c 3) (edge a c 10)))
|
||||
dl-demo-shortest-path-rules)
|
||||
(quote (shortest a c W)))
|
||||
(list {:W 8}))
|
||||
|
||||
(dl-demo-test-set! "shortest unreachable empty"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote ((edge a b 5) (edge b c 3)))
|
||||
dl-demo-shortest-path-rules)
|
||||
(quote (shortest a d W)))
|
||||
(list))
|
||||
|
||||
;; ── Org chart + headcount ─────────────────────────────
|
||||
(dl-demo-test-set! "ceo subordinate transitive"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((manager ic1 mgr1) (manager ic2 mgr1)
|
||||
(manager mgr1 vp1) (manager ic3 vp1)
|
||||
(manager vp1 ceo)))
|
||||
dl-demo-org-rules)
|
||||
(quote (subordinate ceo X)))
|
||||
(list
|
||||
{:X (quote vp1)} {:X (quote mgr1)} {:X (quote ic1)}
|
||||
{:X (quote ic2)} {:X (quote ic3)}))
|
||||
|
||||
(dl-demo-test-set! "ceo headcount = 5"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((manager ic1 mgr1) (manager ic2 mgr1)
|
||||
(manager mgr1 vp1) (manager ic3 vp1)
|
||||
(manager vp1 ceo)))
|
||||
dl-demo-org-rules)
|
||||
(quote (headcount ceo N)))
|
||||
(list {:N 5}))
|
||||
|
||||
(dl-demo-test-set! "mgr1 headcount = 2"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote
|
||||
((manager ic1 mgr1) (manager ic2 mgr1)
|
||||
(manager mgr1 vp1) (manager ic3 vp1)
|
||||
(manager vp1 ceo)))
|
||||
dl-demo-org-rules)
|
||||
(quote (headcount mgr1 N)))
|
||||
(list {:N 2}))
|
||||
|
||||
(dl-demo-test-set! "no access without grant"
|
||||
(dl-query
|
||||
(dl-demo-make
|
||||
(quote ((member dave outsiders) (allowed editors blog)))
|
||||
dl-demo-perm-rules)
|
||||
(quote (can-access X blog)))
|
||||
(list)))))
|
||||
|
||||
(define
|
||||
dl-demo-tests-run!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(set! dl-demo-pass 0)
|
||||
(set! dl-demo-fail 0)
|
||||
(set! dl-demo-failures (list))
|
||||
(dl-demo-run-all!)
|
||||
{:passed dl-demo-pass
|
||||
:failed dl-demo-fail
|
||||
:total (+ dl-demo-pass dl-demo-fail)
|
||||
:failures dl-demo-failures})))
|
||||
463
lib/datalog/tests/eval.sx
Normal file
463
lib/datalog/tests/eval.sx
Normal file
@@ -0,0 +1,463 @@
|
||||
;; lib/datalog/tests/eval.sx — naive evaluation + safety analysis tests.
|
||||
|
||||
(define dl-et-pass 0)
|
||||
(define dl-et-fail 0)
|
||||
(define dl-et-failures (list))
|
||||
|
||||
;; Same deep-equal helper used in other suites.
|
||||
(define
|
||||
dl-et-deep=?
|
||||
(fn
|
||||
(a b)
|
||||
(cond
|
||||
((and (list? a) (list? b))
|
||||
(and (= (len a) (len b)) (dl-et-deq-l? a b 0)))
|
||||
((and (dict? a) (dict? b))
|
||||
(let
|
||||
((ka (keys a)) (kb (keys b)))
|
||||
(and (= (len ka) (len kb)) (dl-et-deq-d? a b ka 0))))
|
||||
((and (number? a) (number? b)) (= a b))
|
||||
(else (equal? a b)))))
|
||||
|
||||
(define
|
||||
dl-et-deq-l?
|
||||
(fn
|
||||
(a b i)
|
||||
(cond
|
||||
((>= i (len a)) true)
|
||||
((not (dl-et-deep=? (nth a i) (nth b i))) false)
|
||||
(else (dl-et-deq-l? a b (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-et-deq-d?
|
||||
(fn
|
||||
(a b ka i)
|
||||
(cond
|
||||
((>= i (len ka)) true)
|
||||
((let ((k (nth ka i))) (not (dl-et-deep=? (get a k) (get b k))))
|
||||
false)
|
||||
(else (dl-et-deq-d? a b ka (+ i 1))))))
|
||||
|
||||
;; Set-equality on lists (order-independent, uses dl-et-deep=?).
|
||||
(define
|
||||
dl-et-set=?
|
||||
(fn
|
||||
(a b)
|
||||
(and (= (len a) (len b)) (dl-et-subset? a b) (dl-et-subset? b a))))
|
||||
|
||||
(define
|
||||
dl-et-subset?
|
||||
(fn
|
||||
(xs ys)
|
||||
(cond
|
||||
((= (len xs) 0) true)
|
||||
((not (dl-et-contains? ys (first xs))) false)
|
||||
(else (dl-et-subset? (rest xs) ys)))))
|
||||
|
||||
(define
|
||||
dl-et-contains?
|
||||
(fn
|
||||
(xs target)
|
||||
(cond
|
||||
((= (len xs) 0) false)
|
||||
((dl-et-deep=? (first xs) target) true)
|
||||
(else (dl-et-contains? (rest xs) target)))))
|
||||
|
||||
(define
|
||||
dl-et-test!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-et-deep=? got expected)
|
||||
(set! dl-et-pass (+ dl-et-pass 1))
|
||||
(do
|
||||
(set! dl-et-fail (+ dl-et-fail 1))
|
||||
(append!
|
||||
dl-et-failures
|
||||
(str name "\n expected: " expected "\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-et-test-set!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-et-set=? got expected)
|
||||
(set! dl-et-pass (+ dl-et-pass 1))
|
||||
(do
|
||||
(set! dl-et-fail (+ dl-et-fail 1))
|
||||
(append!
|
||||
dl-et-failures
|
||||
(str
|
||||
name
|
||||
"\n expected (set): "
|
||||
expected
|
||||
"\n got: "
|
||||
got))))))
|
||||
|
||||
(define
|
||||
dl-et-throws?
|
||||
(fn
|
||||
(thunk)
|
||||
(let
|
||||
((threw false))
|
||||
(do (guard (e (#t (set! threw true))) (thunk)) threw))))
|
||||
|
||||
(define
|
||||
dl-et-run-all!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(dl-et-test-set!
|
||||
"fact lookup any"
|
||||
(dl-query
|
||||
(dl-program "parent(tom, bob). parent(bob, ann).")
|
||||
(list (quote parent) (quote X) (quote Y)))
|
||||
(list {:X (quote tom) :Y (quote bob)} {:X (quote bob) :Y (quote ann)}))
|
||||
(dl-et-test-set!
|
||||
"fact lookup constant arg"
|
||||
(dl-query
|
||||
(dl-program "parent(tom, bob). parent(tom, liz). parent(bob, ann).")
|
||||
(list (quote parent) (quote tom) (quote Y)))
|
||||
(list {:Y (quote bob)} {:Y (quote liz)}))
|
||||
(dl-et-test-set!
|
||||
"no match"
|
||||
(dl-query
|
||||
(dl-program "parent(tom, bob).")
|
||||
(list (quote parent) (quote nobody) (quote X)))
|
||||
(list))
|
||||
(dl-et-test-set!
|
||||
"ancestor closure"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"parent(tom, bob). parent(bob, ann). parent(ann, pat).\n ancestor(X, Y) :- parent(X, Y).\n ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")
|
||||
(list (quote ancestor) (quote tom) (quote X)))
|
||||
(list {:X (quote bob)} {:X (quote ann)} {:X (quote pat)}))
|
||||
(dl-et-test-set!
|
||||
"sibling"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"parent(tom, bob). parent(tom, liz). parent(jane, bob). parent(jane, liz).\n sibling(X, Y) :- parent(P, X), parent(P, Y).")
|
||||
(list (quote sibling) (quote bob) (quote Y)))
|
||||
(list {:Y (quote bob)} {:Y (quote liz)}))
|
||||
(dl-et-test-set!
|
||||
"same-generation"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"parent(tom, bob). parent(tom, liz). parent(bob, ann). parent(liz, joe).\n person(tom). person(bob). person(liz). person(ann). person(joe).\n sg(X, X) :- person(X).\n sg(X, Y) :- parent(P1, X), sg(P1, P2), parent(P2, Y).")
|
||||
(list (quote sg) (quote ann) (quote X)))
|
||||
(list {:X (quote ann)} {:X (quote joe)}))
|
||||
(dl-et-test!
|
||||
"ancestor count"
|
||||
(let
|
||||
((db (dl-program "parent(a, b). parent(b, c). parent(c, d).\n ancestor(X, Y) :- parent(X, Y).\n ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")))
|
||||
(do (dl-saturate! db) (len (dl-relation db "ancestor"))))
|
||||
6)
|
||||
(dl-et-test-set!
|
||||
"grandparent"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"parent(a, b). parent(b, c). parent(c, d).\n grandparent(X, Z) :- parent(X, Y), parent(Y, Z).")
|
||||
(list (quote grandparent) (quote X) (quote Y)))
|
||||
(list {:X (quote a) :Y (quote c)} {:X (quote b) :Y (quote d)}))
|
||||
(dl-et-test!
|
||||
"no recursion infinite loop"
|
||||
(let
|
||||
((db (dl-program "edge(1, 2). edge(2, 3). edge(3, 1).\n reach(X, Y) :- edge(X, Y).\n reach(X, Z) :- edge(X, Y), reach(Y, Z).")))
|
||||
(do (dl-saturate! db) (len (dl-relation db "reach"))))
|
||||
9)
|
||||
;; Rule-shape sanity: empty-list head and non-list body raise
|
||||
;; clear errors rather than crashing inside the saturator.
|
||||
(dl-et-test! "empty head rejected"
|
||||
(dl-et-throws?
|
||||
(fn ()
|
||||
(dl-add-rule! (dl-make-db)
|
||||
{:head (list) :body (list)})))
|
||||
true)
|
||||
|
||||
(dl-et-test! "non-list body rejected"
|
||||
(dl-et-throws?
|
||||
(fn ()
|
||||
(dl-add-rule! (dl-make-db)
|
||||
{:head (list (quote p) (quote X)) :body 42})))
|
||||
true)
|
||||
|
||||
;; Reserved relation names rejected as rule/fact heads.
|
||||
(dl-et-test!
|
||||
"reserved name `not` as head rejected"
|
||||
(dl-et-throws? (fn () (dl-program "not(X) :- p(X).")))
|
||||
true)
|
||||
|
||||
(dl-et-test!
|
||||
"reserved name `count` as head rejected"
|
||||
(dl-et-throws?
|
||||
(fn () (dl-program "count(N, X, p(X)) :- p(X).")))
|
||||
true)
|
||||
|
||||
(dl-et-test!
|
||||
"reserved name `<` as head rejected"
|
||||
(dl-et-throws? (fn () (dl-program "<(X, 5) :- p(X).")))
|
||||
true)
|
||||
|
||||
(dl-et-test!
|
||||
"reserved name `is` as head rejected"
|
||||
(dl-et-throws? (fn () (dl-program "is(N, +(1, 2)) :- p(N).")))
|
||||
true)
|
||||
|
||||
;; Body literal with a reserved-name positive head is rejected.
|
||||
;; The parser only treats outer-level `not(P)` as negation; nested
|
||||
;; `not(not(P))` would otherwise silently parse as a positive call
|
||||
;; to a relation named `not` and succeed vacuously. The safety
|
||||
;; checker now flags this so the user gets a clear error.
|
||||
;; Body literal with a reserved-name positive head is rejected.
|
||||
;; The parser only treats outer-level `not(P)` as negation; nested
|
||||
;; `not(not(P))` would otherwise silently parse as a positive call
|
||||
;; to a relation named `not` and succeed vacuously — so the safety
|
||||
;; checker now flags this to give the user a clear error.
|
||||
(dl-et-test!
|
||||
"nested not(not(...)) rejected"
|
||||
(dl-et-throws?
|
||||
(fn ()
|
||||
(dl-program
|
||||
"banned(a). u(a). vip(X) :- u(X), not(not(banned(X))).")))
|
||||
true)
|
||||
|
||||
;; A dict body literal that isn't `{:neg ...}` is almost always a
|
||||
;; typo — it would otherwise silently fall through to a confusing
|
||||
;; head-var-unbound safety error. Now caught with a clear message.
|
||||
(dl-et-test!
|
||||
"dict body lit without :neg rejected"
|
||||
(dl-et-throws?
|
||||
(fn ()
|
||||
(let ((db (dl-make-db)))
|
||||
(dl-add-rule! db
|
||||
{:head (list (quote p) (quote X))
|
||||
:body (list {:weird "stuff"})}))))
|
||||
true)
|
||||
|
||||
;; Facts may only have simple-term args (number / string / symbol).
|
||||
;; A compound arg like `+(1, 2)` would otherwise be silently
|
||||
;; stored as the unreduced expression `(+ 1 2)` because dl-ground?
|
||||
;; sees no free variables.
|
||||
(dl-et-test!
|
||||
"compound arg in fact rejected"
|
||||
(dl-et-throws? (fn () (dl-program "p(+(1, 2)).")))
|
||||
true)
|
||||
|
||||
;; Rule heads may only have variable or constant args — no
|
||||
;; compounds. Compound heads would be saturated as unreduced
|
||||
;; tuples rather than the arithmetic result the user expected.
|
||||
(dl-et-test!
|
||||
"compound arg in rule head rejected"
|
||||
(dl-et-throws?
|
||||
(fn () (dl-program "n(3). double(*(X, 2)) :- n(X).")))
|
||||
true)
|
||||
|
||||
;; The anonymous-variable renamer used to start at `_anon1`
|
||||
;; unconditionally; a rule that wrote `q(_anon1) :- p(_anon1, _)`
|
||||
;; (the user picking the same name the renamer would generate)
|
||||
;; would see the `_` renamed to `_anon1` too, collapsing the
|
||||
;; two positions in `p(_anon1, _)` to a single var. Now the
|
||||
;; renamer scans the rule for the max `_anon<N>` and starts past
|
||||
;; it, so user-written names of that form are preserved.
|
||||
(dl-et-test-set! "anonymous-rename avoids user `_anon` collision"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(a, b). p(c, d). q(_anon1) :- p(_anon1, _).")
|
||||
(quote (q X)))
|
||||
(list {:X (quote a)} {:X (quote c)}))
|
||||
|
||||
(dl-et-test!
|
||||
"unsafe head var"
|
||||
(dl-et-throws? (fn () (dl-program "p(X, Y) :- q(X).")))
|
||||
true)
|
||||
(dl-et-test!
|
||||
"unsafe — empty body"
|
||||
(dl-et-throws? (fn () (dl-program "p(X) :- .")))
|
||||
true)
|
||||
;; Underscore in head is unsafe — it's a fresh existential per
|
||||
;; occurrence after Phase 5d's anonymous-var renaming, and there's
|
||||
;; nothing in the body to bind it. (Old behavior accepted this by
|
||||
;; treating '_' as a literal name to skip; the renaming made it an
|
||||
;; ordinary unbound variable.)
|
||||
(dl-et-test!
|
||||
"underscore in head — unsafe"
|
||||
(dl-et-throws? (fn () (dl-program "p(X, _) :- q(X).")))
|
||||
true)
|
||||
(dl-et-test!
|
||||
"underscore in body only — safe"
|
||||
(dl-et-throws? (fn () (dl-program "p(X) :- q(X, _).")))
|
||||
false)
|
||||
(dl-et-test!
|
||||
"var only in head — unsafe"
|
||||
(dl-et-throws? (fn () (dl-program "p(X, Y) :- q(Z).")))
|
||||
true)
|
||||
(dl-et-test!
|
||||
"head var bound by body"
|
||||
(dl-et-throws? (fn () (dl-program "p(X) :- q(X).")))
|
||||
false)
|
||||
(dl-et-test!
|
||||
"head subset of body"
|
||||
(dl-et-throws?
|
||||
(fn
|
||||
()
|
||||
(dl-program
|
||||
"edge(a,b). edge(b,c). reach(X, Z) :- edge(X, Y), edge(Y, Z).")))
|
||||
false)
|
||||
|
||||
;; Anonymous variables: each occurrence must be independent.
|
||||
(dl-et-test-set! "anon vars in rule are independent"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(a, b). p(c, d). q(X) :- p(X, _), p(_, Y).")
|
||||
(list (quote q) (quote X)))
|
||||
(list {:X (quote a)} {:X (quote c)}))
|
||||
|
||||
(dl-et-test-set! "anon vars in goal are independent"
|
||||
(dl-query
|
||||
(dl-program "p(1, 2, 3). p(4, 5, 6).")
|
||||
(list (quote p) (quote _) (quote X) (quote _)))
|
||||
(list {:X 2} {:X 5}))
|
||||
|
||||
;; dl-summary: relation -> tuple-count for inspection.
|
||||
(dl-et-test! "dl-summary basic"
|
||||
(dl-summary
|
||||
(let
|
||||
((db (dl-program "p(1). p(2). q(3).")))
|
||||
(do (dl-saturate! db) db)))
|
||||
{:p 2 :q 1})
|
||||
|
||||
(dl-et-test! "dl-summary empty IDB shown"
|
||||
(dl-summary
|
||||
(let
|
||||
((db (dl-program "r(X) :- s(X).")))
|
||||
(do (dl-saturate! db) db)))
|
||||
{:r 0})
|
||||
|
||||
(dl-et-test! "dl-summary mixed EDB and IDB"
|
||||
(dl-summary
|
||||
(let
|
||||
((db (dl-program
|
||||
"parent(a, b).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")))
|
||||
(do (dl-saturate! db) db)))
|
||||
{:parent 1 :ancestor 1})
|
||||
|
||||
(dl-et-test! "dl-summary empty db"
|
||||
(dl-summary (dl-make-db))
|
||||
{})
|
||||
|
||||
;; Strategy hook: default semi-naive; :magic accepted but
|
||||
;; falls back to semi-naive (the transformation itself is
|
||||
;; deferred — Phase 6 in plan).
|
||||
(dl-et-test! "default strategy"
|
||||
(dl-get-strategy (dl-make-db))
|
||||
:semi-naive)
|
||||
|
||||
(dl-et-test! "set strategy"
|
||||
(let ((db (dl-make-db)))
|
||||
(do (dl-set-strategy! db :magic) (dl-get-strategy db)))
|
||||
:magic)
|
||||
|
||||
;; Unknown strategy values are rejected so typos don't silently
|
||||
;; fall back to the default.
|
||||
(dl-et-test!
|
||||
"unknown strategy rejected"
|
||||
(dl-et-throws?
|
||||
(fn ()
|
||||
(let ((db (dl-make-db)))
|
||||
(dl-set-strategy! db :semi_naive))))
|
||||
true)
|
||||
|
||||
;; dl-saturated?: no-work-left predicate.
|
||||
(dl-et-test! "saturated? after saturation"
|
||||
(let ((db (dl-program
|
||||
"parent(a, b).
|
||||
ancestor(X, Y) :- parent(X, Y).")))
|
||||
(do (dl-saturate! db) (dl-saturated? db)))
|
||||
true)
|
||||
|
||||
(dl-et-test! "saturated? before saturation"
|
||||
(let ((db (dl-program
|
||||
"parent(a, b).
|
||||
ancestor(X, Y) :- parent(X, Y).")))
|
||||
(dl-saturated? db))
|
||||
false)
|
||||
|
||||
;; Disjunction via multiple rules — Datalog has no `;` in
|
||||
;; body, so disjunction is expressed as separate rules with
|
||||
;; the same head. Here plant_based(X) is satisfied by either
|
||||
;; vegan(X) or vegetarian(X).
|
||||
(dl-et-test-set! "disjunction via multiple rules"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"vegan(alice). vegetarian(bob). meat_eater(carol).
|
||||
plant_based(X) :- vegan(X).
|
||||
plant_based(X) :- vegetarian(X).")
|
||||
(list (quote plant_based) (quote X)))
|
||||
(list {:X (quote alice)} {:X (quote bob)}))
|
||||
|
||||
;; Bipartite-style join: pair-of-friends who share a hobby.
|
||||
;; Three-relation join exercising the planner's join order.
|
||||
(dl-et-test-set! "bipartite friends-with-hobby"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"hobby(alice, climb). hobby(bob, paint).
|
||||
hobby(carol, climb).
|
||||
friend(alice, carol). friend(bob, alice).
|
||||
match(A, B, H) :- friend(A, B), hobby(A, H), hobby(B, H).")
|
||||
(list (quote match) (quote A) (quote B) (quote H)))
|
||||
(list {:A (quote alice) :B (quote carol) :H (quote climb)}))
|
||||
|
||||
;; Repeated variable (diagonal): p(X, X) only matches tuples
|
||||
;; whose two args are equal. The unifier handles this via the
|
||||
;; subst chain — first occurrence binds X, second occurrence
|
||||
;; checks against the binding.
|
||||
(dl-et-test-set! "diagonal query"
|
||||
(dl-query
|
||||
(dl-program "p(1, 1). p(2, 3). p(4, 4). p(5, 5).")
|
||||
(list (quote p) (quote X) (quote X)))
|
||||
(list {:X 1} {:X 4} {:X 5}))
|
||||
|
||||
;; A relation can be both EDB-seeded and rule-derived;
|
||||
;; saturate combines facts + derivations.
|
||||
(dl-et-test-set! "mixed EDB + IDB same relation"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"link(a, b). link(c, d). link(e, c).
|
||||
via(a, e).
|
||||
link(X, Y) :- via(X, M), link(M, Y).")
|
||||
(list (quote link) (quote a) (quote X)))
|
||||
(list {:X (quote b)} {:X (quote c)}))
|
||||
|
||||
(dl-et-test! "saturated? after assert"
|
||||
(let ((db (dl-program
|
||||
"parent(a, b).
|
||||
ancestor(X, Y) :- parent(X, Y).")))
|
||||
(do
|
||||
(dl-saturate! db)
|
||||
(dl-add-fact! db (list (quote parent) (quote b) (quote c)))
|
||||
(dl-saturated? db)))
|
||||
false)
|
||||
|
||||
(dl-et-test-set! "magic-set still derives correctly"
|
||||
(let
|
||||
((db (dl-program
|
||||
"parent(a, b). parent(b, c).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")))
|
||||
(do
|
||||
(dl-set-strategy! db :magic)
|
||||
(dl-query db (list (quote ancestor) (quote a) (quote X)))))
|
||||
(list {:X (quote b)} {:X (quote c)})))))
|
||||
|
||||
(define
|
||||
dl-eval-tests-run!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(set! dl-et-pass 0)
|
||||
(set! dl-et-fail 0)
|
||||
(set! dl-et-failures (list))
|
||||
(dl-et-run-all!)
|
||||
{:failures dl-et-failures :total (+ dl-et-pass dl-et-fail) :passed dl-et-pass :failed dl-et-fail})))
|
||||
528
lib/datalog/tests/magic.sx
Normal file
528
lib/datalog/tests/magic.sx
Normal file
@@ -0,0 +1,528 @@
|
||||
;; lib/datalog/tests/magic.sx — adornment + SIPS analysis tests.
|
||||
|
||||
(define dl-mt-pass 0)
|
||||
(define dl-mt-fail 0)
|
||||
(define dl-mt-failures (list))
|
||||
|
||||
(define
|
||||
dl-mt-deep=?
|
||||
(fn
|
||||
(a b)
|
||||
(cond
|
||||
((and (list? a) (list? b))
|
||||
(and (= (len a) (len b)) (dl-mt-deq-l? a b 0)))
|
||||
((and (dict? a) (dict? b))
|
||||
(let ((ka (keys a)) (kb (keys b)))
|
||||
(and (= (len ka) (len kb)) (dl-mt-deq-d? a b ka 0))))
|
||||
((and (number? a) (number? b)) (= a b))
|
||||
(else (equal? a b)))))
|
||||
|
||||
(define
|
||||
dl-mt-deq-l?
|
||||
(fn
|
||||
(a b i)
|
||||
(cond
|
||||
((>= i (len a)) true)
|
||||
((not (dl-mt-deep=? (nth a i) (nth b i))) false)
|
||||
(else (dl-mt-deq-l? a b (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-mt-deq-d?
|
||||
(fn
|
||||
(a b ka i)
|
||||
(cond
|
||||
((>= i (len ka)) true)
|
||||
((let ((k (nth ka i)))
|
||||
(not (dl-mt-deep=? (get a k) (get b k))))
|
||||
false)
|
||||
(else (dl-mt-deq-d? a b ka (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-mt-test!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-mt-deep=? got expected)
|
||||
(set! dl-mt-pass (+ dl-mt-pass 1))
|
||||
(do
|
||||
(set! dl-mt-fail (+ dl-mt-fail 1))
|
||||
(append!
|
||||
dl-mt-failures
|
||||
(str
|
||||
name
|
||||
"\n expected: " expected
|
||||
"\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-mt-run-all!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
;; Goal adornment.
|
||||
(dl-mt-test! "adorn 0-ary"
|
||||
(dl-adorn-goal (list (quote ready)))
|
||||
"")
|
||||
(dl-mt-test! "adorn all bound"
|
||||
(dl-adorn-goal (list (quote p) 1 2 3))
|
||||
"bbb")
|
||||
(dl-mt-test! "adorn all free"
|
||||
(dl-adorn-goal (list (quote p) (quote X) (quote Y)))
|
||||
"ff")
|
||||
(dl-mt-test! "adorn mixed"
|
||||
(dl-adorn-goal (list (quote ancestor) (quote tom) (quote X)))
|
||||
"bf")
|
||||
(dl-mt-test! "adorn const var const"
|
||||
(dl-adorn-goal (list (quote p) (quote a) (quote X) (quote b)))
|
||||
"bfb")
|
||||
|
||||
;; dl-adorn-lit with explicit bound set.
|
||||
(dl-mt-test! "adorn lit with bound"
|
||||
(dl-adorn-lit (list (quote p) (quote X) (quote Y)) (list "X"))
|
||||
"bf")
|
||||
|
||||
;; Rule SIPS — chain ancestor.
|
||||
(dl-mt-test! "sips chain ancestor bf"
|
||||
(dl-rule-sips
|
||||
{:head (list (quote ancestor) (quote X) (quote Z))
|
||||
:body (list (list (quote parent) (quote X) (quote Y))
|
||||
(list (quote ancestor) (quote Y) (quote Z)))}
|
||||
"bf")
|
||||
(list
|
||||
{:lit (list (quote parent) (quote X) (quote Y)) :adornment "bf"}
|
||||
{:lit (list (quote ancestor) (quote Y) (quote Z)) :adornment "bf"}))
|
||||
|
||||
;; SIPS — head fully bound.
|
||||
(dl-mt-test! "sips head bb"
|
||||
(dl-rule-sips
|
||||
{:head (list (quote q) (quote X) (quote Y))
|
||||
:body (list (list (quote p) (quote X) (quote Z))
|
||||
(list (quote r) (quote Z) (quote Y)))}
|
||||
"bb")
|
||||
(list
|
||||
{:lit (list (quote p) (quote X) (quote Z)) :adornment "bf"}
|
||||
{:lit (list (quote r) (quote Z) (quote Y)) :adornment "bb"}))
|
||||
|
||||
;; SIPS — comparison; vars must be bound by prior body lit.
|
||||
(dl-mt-test! "sips with comparison"
|
||||
(dl-rule-sips
|
||||
{:head (list (quote q) (quote X))
|
||||
:body (list (list (quote p) (quote X))
|
||||
(list (string->symbol "<") (quote X) 5))}
|
||||
"f")
|
||||
(list
|
||||
{:lit (list (quote p) (quote X)) :adornment "f"}
|
||||
{:lit (list (string->symbol "<") (quote X) 5) :adornment "bb"}))
|
||||
|
||||
;; SIPS — `is` binds its left arg.
|
||||
(dl-mt-test! "sips with is"
|
||||
(dl-rule-sips
|
||||
{:head (list (quote q) (quote X) (quote Y))
|
||||
:body (list (list (quote p) (quote X))
|
||||
(list (quote is) (quote Y) (list (string->symbol "+") (quote X) 1)))}
|
||||
"ff")
|
||||
(list
|
||||
{:lit (list (quote p) (quote X)) :adornment "f"}
|
||||
{:lit (list (quote is) (quote Y)
|
||||
(list (string->symbol "+") (quote X) 1))
|
||||
:adornment "fb"}))
|
||||
|
||||
;; Magic predicate naming.
|
||||
(dl-mt-test! "magic-rel-name"
|
||||
(dl-magic-rel-name "ancestor" "bf")
|
||||
"magic_ancestor^bf")
|
||||
|
||||
;; Bound-args extraction.
|
||||
(dl-mt-test! "bound-args bf"
|
||||
(dl-bound-args (list (quote ancestor) (quote tom) (quote X)) "bf")
|
||||
(list (quote tom)))
|
||||
|
||||
(dl-mt-test! "bound-args mixed"
|
||||
(dl-bound-args (list (quote p) 1 (quote Y) 3) "bfb")
|
||||
(list 1 3))
|
||||
|
||||
(dl-mt-test! "bound-args all-free"
|
||||
(dl-bound-args (list (quote p) (quote X) (quote Y)) "ff")
|
||||
(list))
|
||||
|
||||
;; Magic literal construction.
|
||||
(dl-mt-test! "magic-lit"
|
||||
(dl-magic-lit "ancestor" "bf" (list (quote tom)))
|
||||
(list (string->symbol "magic_ancestor^bf") (quote tom)))
|
||||
|
||||
;; Magic-sets rewriter: structural sanity.
|
||||
(dl-mt-test! "rewrite ancestor produces seed"
|
||||
(let
|
||||
((rules
|
||||
(list
|
||||
{:head (list (quote ancestor) (quote X) (quote Y))
|
||||
:body (list (list (quote parent) (quote X) (quote Y)))}
|
||||
{:head (list (quote ancestor) (quote X) (quote Z))
|
||||
:body
|
||||
(list (list (quote parent) (quote X) (quote Y))
|
||||
(list (quote ancestor) (quote Y) (quote Z)))})))
|
||||
(get
|
||||
(dl-magic-rewrite rules "ancestor" "bf" (list (quote a)))
|
||||
:seed))
|
||||
(list (string->symbol "magic_ancestor^bf") (quote a)))
|
||||
|
||||
;; Equivalence: rewritten program derives same ancestor tuples.
|
||||
;; In a chain a→b→c→d, magic-rewritten run still derives all
|
||||
;; ancestor pairs reachable from any node a/b/c/d propagated via
|
||||
;; magic_ancestor^bf — i.e. the full closure (6 tuples). Magic
|
||||
;; saves work only when the EDB has irrelevant nodes outside
|
||||
;; the seed's transitive cone.
|
||||
(dl-mt-test! "magic-rewritten ancestor count"
|
||||
(let
|
||||
((rules
|
||||
(list
|
||||
{:head (list (quote ancestor) (quote X) (quote Y))
|
||||
:body (list (list (quote parent) (quote X) (quote Y)))}
|
||||
{:head (list (quote ancestor) (quote X) (quote Z))
|
||||
:body
|
||||
(list (list (quote parent) (quote X) (quote Y))
|
||||
(list (quote ancestor) (quote Y) (quote Z)))}))
|
||||
(edb (list
|
||||
(list (quote parent) (quote a) (quote b))
|
||||
(list (quote parent) (quote b) (quote c))
|
||||
(list (quote parent) (quote c) (quote d)))))
|
||||
(let
|
||||
((rewritten (dl-magic-rewrite rules "ancestor" "bf" (list (quote a))))
|
||||
(db (dl-make-db)))
|
||||
(do
|
||||
(for-each (fn (f) (dl-add-fact! db f)) edb)
|
||||
(dl-add-fact! db (get rewritten :seed))
|
||||
(for-each (fn (r) (dl-add-rule! db r)) (get rewritten :rules))
|
||||
(dl-saturate! db)
|
||||
(len (dl-relation db "ancestor")))))
|
||||
6)
|
||||
|
||||
;; dl-magic-query: end-to-end driver, doesn't mutate caller's db.
|
||||
;; Magic over a rule with negated body literal — propagation
|
||||
;; rules generated only for positive lits; negated lits pass
|
||||
;; through unchanged.
|
||||
(dl-mt-test! "magic over rule with negation"
|
||||
(let
|
||||
((db (dl-program
|
||||
"u(a). u(b). u(c). banned(b).
|
||||
active(X) :- u(X), not(banned(X)).")))
|
||||
(let
|
||||
((semi (dl-query db (list (quote active) (quote X))))
|
||||
(magic (dl-magic-query db (list (quote active) (quote X)))))
|
||||
(= (len semi) (len magic))))
|
||||
true)
|
||||
|
||||
;; All-bound query (existence check) generates an "bb"
|
||||
;; adornment chain. Verifies the rewriter walks multiple
|
||||
;; (rel, adn) pairs through the worklist.
|
||||
(dl-mt-test! "magic existence check via bb"
|
||||
(let
|
||||
((db (dl-program
|
||||
"parent(a, b). parent(b, c). parent(c, d).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")))
|
||||
(let
|
||||
((found (dl-magic-query
|
||||
db (list (quote ancestor) (quote a) (quote c))))
|
||||
(missing (dl-magic-query
|
||||
db (list (quote ancestor) (quote a) (quote z)))))
|
||||
(and (= (len found) 1) (= (len missing) 0))))
|
||||
true)
|
||||
|
||||
;; Magic equivalence on the federation demo.
|
||||
(dl-mt-test! "magic ≡ semi on foaf demo"
|
||||
(let
|
||||
((db (dl-program-data
|
||||
(quote ((follows alice bob)
|
||||
(follows bob carol)
|
||||
(follows alice dave)))
|
||||
dl-demo-federation-rules)))
|
||||
(let
|
||||
((semi (dl-query db (quote (foaf alice X))))
|
||||
(magic (dl-magic-query db (quote (foaf alice X)))))
|
||||
(= (len semi) (len magic))))
|
||||
true)
|
||||
|
||||
;; Shape validation: dl-magic-query rejects non-list / non-
|
||||
;; dict goal shapes cleanly rather than crashing in `rest`.
|
||||
(dl-mt-test! "magic rejects string goal"
|
||||
(let ((threw false))
|
||||
(do
|
||||
(guard (e (#t (set! threw true)))
|
||||
(dl-magic-query (dl-make-db) "foo"))
|
||||
threw))
|
||||
true)
|
||||
|
||||
(dl-mt-test! "magic rejects bare dict goal"
|
||||
(let ((threw false))
|
||||
(do
|
||||
(guard (e (#t (set! threw true)))
|
||||
(dl-magic-query (dl-make-db) {:foo "bar"}))
|
||||
threw))
|
||||
true)
|
||||
|
||||
;; 3-stratum program under magic — distinct rule heads at
|
||||
;; strata 0/1/2 must all rewrite via the worklist.
|
||||
(dl-mt-test! "magic 3-stratum program"
|
||||
(let
|
||||
((db (dl-program
|
||||
"a(1). a(2). a(3). b(2).
|
||||
c(X) :- a(X), not(b(X)).
|
||||
d(X) :- c(X), not(banned(X)).
|
||||
banned(3).")))
|
||||
(let
|
||||
((semi (dl-query db (list (quote d) (quote X))))
|
||||
(magic (dl-magic-query db (list (quote d) (quote X)))))
|
||||
(= (len semi) (len magic))))
|
||||
true)
|
||||
|
||||
;; Aggregate -> derived -> threshold chain via magic.
|
||||
(dl-mt-test! "magic aggregate-derived chain"
|
||||
(let
|
||||
((db (dl-program
|
||||
"src(1). src(2). src(3).
|
||||
cnt(N) :- count(N, X, src(X)).
|
||||
active(N) :- cnt(N), >=(N, 2).")))
|
||||
(let
|
||||
((semi (dl-query db (list (quote active) (quote N))))
|
||||
(magic (dl-magic-query db (list (quote active) (quote N)))))
|
||||
(= (len semi) (len magic))))
|
||||
true)
|
||||
|
||||
;; Multi-relation rewrite chain: query r4 → propagate to r3,
|
||||
;; r2, r1, a. The worklist must process all of them; an
|
||||
;; earlier bug stopped after only the head pair.
|
||||
(dl-mt-test! "magic chain through 4 rule levels"
|
||||
(let
|
||||
((db (dl-program
|
||||
"a(1). a(2). r1(X) :- a(X). r2(X) :- r1(X).
|
||||
r3(X) :- r2(X). r4(X) :- r3(X).")))
|
||||
(= 2 (len (dl-magic-query db (list (quote r4) (quote X))))))
|
||||
true)
|
||||
|
||||
;; Shortest-path demo via magic — exercises the rewriter
|
||||
;; against rules that mix recursive positive lits with an
|
||||
;; aggregate body literal.
|
||||
(dl-mt-test! "magic on shortest-path demo"
|
||||
(let
|
||||
((db (dl-program-data
|
||||
(quote ((edge a b 5) (edge b c 3) (edge a c 10)))
|
||||
dl-demo-shortest-path-rules)))
|
||||
(let
|
||||
((semi (dl-query db (quote (shortest a c W))))
|
||||
(magic (dl-magic-query db (quote (shortest a c W)))))
|
||||
(and (= (len semi) (len magic))
|
||||
(= (len semi) 1))))
|
||||
true)
|
||||
|
||||
;; Same relation called with different adornment patterns
|
||||
;; in different rules. The worklist must enqueue and process
|
||||
;; each (rel, adornment) pair.
|
||||
(dl-mt-test! "magic with multi-adornment same relation"
|
||||
(let
|
||||
((db (dl-program
|
||||
"parent(p1, alice). parent(p2, bob).
|
||||
parent(g, p1). parent(g, p2).
|
||||
sibling(P1, P2) :- parent(G, P1), parent(G, P2),
|
||||
!=(P1, P2).
|
||||
cousin(X, Y) :- parent(P1, X), parent(P2, Y),
|
||||
sibling(P1, P2).")))
|
||||
(let
|
||||
((semi (dl-query db (list (quote cousin) (quote alice) (quote Y))))
|
||||
(magic (dl-magic-query db (list (quote cousin) (quote alice) (quote Y)))))
|
||||
(= (len semi) (len magic))))
|
||||
true)
|
||||
|
||||
;; Magic over a rule whose body contains an aggregate.
|
||||
;; The rewriter passes aggregate body lits through unchanged
|
||||
;; (no propagation generated for them), so semi-naive's count
|
||||
;; logic still fires correctly under the rewritten program.
|
||||
(dl-mt-test! "magic over rule with aggregate body"
|
||||
(let
|
||||
((db (dl-program
|
||||
"post(p1). post(p2). post(p3).
|
||||
liked(u1, p1). liked(u2, p1). liked(u3, p1).
|
||||
liked(u1, p2).
|
||||
rich(P) :- post(P), count(N, U, liked(U, P)),
|
||||
>=(N, 2).")))
|
||||
(let
|
||||
((semi (dl-query db (list (quote rich) (quote P))))
|
||||
(magic (dl-magic-query db (list (quote rich) (quote P)))))
|
||||
(= (len semi) (len magic))))
|
||||
true)
|
||||
|
||||
;; Mixed EDB + IDB: a relation can be both EDB-seeded and
|
||||
;; rule-derived. dl-magic-query must include the EDB portion
|
||||
;; even though the relation has rules.
|
||||
(dl-mt-test! "magic mixed EDB+IDB"
|
||||
(len
|
||||
(dl-magic-query
|
||||
(dl-program
|
||||
"link(a, b). link(c, d). link(e, c).
|
||||
via(a, e).
|
||||
link(X, Y) :- via(X, M), link(M, Y).")
|
||||
(list (quote link) (quote a) (quote X))))
|
||||
2)
|
||||
|
||||
;; dl-magic-query falls back to dl-query for built-in,
|
||||
;; aggregate, and negation goals (the magic seed would
|
||||
;; otherwise be non-ground).
|
||||
(dl-mt-test! "magic-query falls back on aggregate"
|
||||
(let
|
||||
((r (dl-magic-query
|
||||
(dl-program "p(1). p(2). p(3).")
|
||||
(list (quote count) (quote N) (quote X)
|
||||
(list (quote p) (quote X))))))
|
||||
(and (= (len r) 1) (= (get (first r) "N") 3)))
|
||||
true)
|
||||
|
||||
(dl-mt-test! "magic-query equivalent to dl-query"
|
||||
(let
|
||||
((db (dl-program
|
||||
"parent(a, b). parent(b, c). parent(c, d).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")))
|
||||
(let
|
||||
((semi (dl-query db (list (quote ancestor) (quote a) (quote X))))
|
||||
(magic (dl-magic-query
|
||||
db (list (quote ancestor) (quote a) (quote X)))))
|
||||
(= (len semi) (len magic))))
|
||||
true)
|
||||
|
||||
;; The magic rewriter passes aggregate body lits through
|
||||
;; unchanged, so an aggregate over an IDB relation would see an
|
||||
;; empty inner-goal in the magic db unless the IDB is already
|
||||
;; materialised. dl-magic-query now pre-saturates the source db
|
||||
;; to guarantee equivalence with dl-query for every stratified
|
||||
;; program. Previously this returned `({:N 0})` because `active`
|
||||
;; (IDB, derived through negation) was never derived in the
|
||||
;; magic db.
|
||||
(dl-mt-test! "magic over aggregate-of-IDB matches vanilla"
|
||||
(let
|
||||
((src
|
||||
"u(a). u(b). u(c). u(d). banned(b). banned(d).
|
||||
active(X) :- u(X), not(banned(X)).
|
||||
n(N) :- count(N, X, active(X))."))
|
||||
(let
|
||||
((vanilla (dl-eval src "?- n(N)."))
|
||||
(magic (dl-eval-magic src "?- n(N).")))
|
||||
(and (= (len vanilla) 1)
|
||||
(= (len magic) 1)
|
||||
(= (get (first vanilla) "N")
|
||||
(get (first magic) "N")))))
|
||||
true)
|
||||
|
||||
;; magic-query doesn't mutate caller db.
|
||||
(dl-mt-test! "magic-query preserves caller db"
|
||||
(let
|
||||
((db (dl-program
|
||||
"parent(a, b). parent(b, c).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")))
|
||||
(let
|
||||
((rules-before (len (dl-rules db))))
|
||||
(do
|
||||
(dl-magic-query db (list (quote ancestor) (quote a) (quote X)))
|
||||
(= rules-before (len (dl-rules db))))))
|
||||
true)
|
||||
|
||||
;; Magic-sets benefit: query touches only one cluster of a
|
||||
;; multi-component graph. Semi-naive derives the full closure
|
||||
;; over both clusters; magic only the seeded one.
|
||||
;; Magic-vs-semi work shape: chain of 12. Semi-naive
|
||||
;; derives the full closure (78 = 12·13/2). A magic query
|
||||
;; rooted at node 0 returns the 12 descendants only —
|
||||
;; demonstrating that magic limits derivation to the
|
||||
;; query's transitive cone.
|
||||
(dl-mt-test! "magic vs semi work-shape on chain-12"
|
||||
(let
|
||||
((source (str
|
||||
"parent(0, 1). parent(1, 2). parent(2, 3). "
|
||||
"parent(3, 4). parent(4, 5). parent(5, 6). "
|
||||
"parent(6, 7). parent(7, 8). parent(8, 9). "
|
||||
"parent(9, 10). parent(10, 11). parent(11, 12). "
|
||||
"ancestor(X, Y) :- parent(X, Y). "
|
||||
"ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")))
|
||||
(let
|
||||
((db1 (dl-make-db)) (db2 (dl-make-db)))
|
||||
(do
|
||||
(dl-load-program! db1 source)
|
||||
(dl-saturate! db1)
|
||||
(dl-load-program! db2 source)
|
||||
(let
|
||||
((semi-count (len (dl-relation db1 "ancestor")))
|
||||
(magic-count
|
||||
(len (dl-magic-query
|
||||
db2 (list (quote ancestor) 0 (quote X))))))
|
||||
;; Magic returns only descendants of 0 (12 of them).
|
||||
(and (= semi-count 78) (= magic-count 12))))))
|
||||
true)
|
||||
|
||||
;; Magic + arithmetic: rules with `is` clauses pass through
|
||||
;; the rewriter unchanged (built-ins aren't propagated).
|
||||
(dl-mt-test! "magic preserves arithmetic"
|
||||
(let
|
||||
((source "n(1). n(2). n(3).
|
||||
doubled(X, Y) :- n(X), is(Y, *(X, 2))."))
|
||||
(let
|
||||
((semi (dl-eval source "?- doubled(2, Y)."))
|
||||
(magic (dl-eval-magic source "?- doubled(2, Y).")))
|
||||
(= (len semi) (len magic))))
|
||||
true)
|
||||
|
||||
(dl-mt-test! "magic skips irrelevant clusters"
|
||||
(let
|
||||
;; Two disjoint chains. Query is rooted in cluster 1.
|
||||
((db (dl-program
|
||||
"parent(a, b). parent(b, c).
|
||||
parent(x, y). parent(y, z).
|
||||
ancestor(X, Y) :- parent(X, Y).
|
||||
ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")))
|
||||
(do
|
||||
(dl-saturate! db)
|
||||
(let
|
||||
((semi-count (len (dl-relation db "ancestor")))
|
||||
(magic-results
|
||||
(dl-magic-query
|
||||
db (list (quote ancestor) (quote a) (quote X)))))
|
||||
;; Semi-naive derives 6 (3 in each cluster). Magic
|
||||
;; gives 3 query results (a's reachable: b, c).
|
||||
(and (= semi-count 6) (= (len magic-results) 2)))))
|
||||
true)
|
||||
|
||||
(dl-mt-test! "magic-rewritten finds same answers"
|
||||
(let
|
||||
((rules
|
||||
(list
|
||||
{:head (list (quote ancestor) (quote X) (quote Y))
|
||||
:body (list (list (quote parent) (quote X) (quote Y)))}
|
||||
{:head (list (quote ancestor) (quote X) (quote Z))
|
||||
:body
|
||||
(list (list (quote parent) (quote X) (quote Y))
|
||||
(list (quote ancestor) (quote Y) (quote Z)))}))
|
||||
(edb (list
|
||||
(list (quote parent) (quote a) (quote b))
|
||||
(list (quote parent) (quote b) (quote c)))))
|
||||
(let
|
||||
((rewritten (dl-magic-rewrite rules "ancestor" "bf" (list (quote a))))
|
||||
(db (dl-make-db)))
|
||||
(do
|
||||
(for-each (fn (f) (dl-add-fact! db f)) edb)
|
||||
(dl-add-fact! db (get rewritten :seed))
|
||||
(for-each (fn (r) (dl-add-rule! db r)) (get rewritten :rules))
|
||||
(dl-saturate! db)
|
||||
(len (dl-query db (list (quote ancestor) (quote a) (quote X)))))))
|
||||
2))))
|
||||
|
||||
(define
|
||||
dl-magic-tests-run!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(set! dl-mt-pass 0)
|
||||
(set! dl-mt-fail 0)
|
||||
(set! dl-mt-failures (list))
|
||||
(dl-mt-run-all!)
|
||||
{:passed dl-mt-pass
|
||||
:failed dl-mt-fail
|
||||
:total (+ dl-mt-pass dl-mt-fail)
|
||||
:failures dl-mt-failures})))
|
||||
252
lib/datalog/tests/negation.sx
Normal file
252
lib/datalog/tests/negation.sx
Normal file
@@ -0,0 +1,252 @@
|
||||
;; lib/datalog/tests/negation.sx — stratified negation tests.
|
||||
|
||||
(define dl-nt-pass 0)
|
||||
(define dl-nt-fail 0)
|
||||
(define dl-nt-failures (list))
|
||||
|
||||
(define
|
||||
dl-nt-deep=?
|
||||
(fn
|
||||
(a b)
|
||||
(cond
|
||||
((and (list? a) (list? b))
|
||||
(and (= (len a) (len b)) (dl-nt-deq-l? a b 0)))
|
||||
((and (dict? a) (dict? b))
|
||||
(let ((ka (keys a)) (kb (keys b)))
|
||||
(and (= (len ka) (len kb)) (dl-nt-deq-d? a b ka 0))))
|
||||
((and (number? a) (number? b)) (= a b))
|
||||
(else (equal? a b)))))
|
||||
|
||||
(define
|
||||
dl-nt-deq-l?
|
||||
(fn
|
||||
(a b i)
|
||||
(cond
|
||||
((>= i (len a)) true)
|
||||
((not (dl-nt-deep=? (nth a i) (nth b i))) false)
|
||||
(else (dl-nt-deq-l? a b (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-nt-deq-d?
|
||||
(fn
|
||||
(a b ka i)
|
||||
(cond
|
||||
((>= i (len ka)) true)
|
||||
((let ((k (nth ka i)))
|
||||
(not (dl-nt-deep=? (get a k) (get b k))))
|
||||
false)
|
||||
(else (dl-nt-deq-d? a b ka (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-nt-set=?
|
||||
(fn
|
||||
(a b)
|
||||
(and
|
||||
(= (len a) (len b))
|
||||
(dl-nt-subset? a b)
|
||||
(dl-nt-subset? b a))))
|
||||
|
||||
(define
|
||||
dl-nt-subset?
|
||||
(fn
|
||||
(xs ys)
|
||||
(cond
|
||||
((= (len xs) 0) true)
|
||||
((not (dl-nt-contains? ys (first xs))) false)
|
||||
(else (dl-nt-subset? (rest xs) ys)))))
|
||||
|
||||
(define
|
||||
dl-nt-contains?
|
||||
(fn
|
||||
(xs target)
|
||||
(cond
|
||||
((= (len xs) 0) false)
|
||||
((dl-nt-deep=? (first xs) target) true)
|
||||
(else (dl-nt-contains? (rest xs) target)))))
|
||||
|
||||
(define
|
||||
dl-nt-test!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-nt-deep=? got expected)
|
||||
(set! dl-nt-pass (+ dl-nt-pass 1))
|
||||
(do
|
||||
(set! dl-nt-fail (+ dl-nt-fail 1))
|
||||
(append!
|
||||
dl-nt-failures
|
||||
(str
|
||||
name
|
||||
"\n expected: " expected
|
||||
"\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-nt-test-set!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-nt-set=? got expected)
|
||||
(set! dl-nt-pass (+ dl-nt-pass 1))
|
||||
(do
|
||||
(set! dl-nt-fail (+ dl-nt-fail 1))
|
||||
(append!
|
||||
dl-nt-failures
|
||||
(str
|
||||
name
|
||||
"\n expected (set): " expected
|
||||
"\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-nt-throws?
|
||||
(fn
|
||||
(thunk)
|
||||
(let
|
||||
((threw false))
|
||||
(do
|
||||
(guard
|
||||
(e (#t (set! threw true)))
|
||||
(thunk))
|
||||
threw))))
|
||||
|
||||
(define
|
||||
dl-nt-run-all!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
;; Negation against EDB-only relation.
|
||||
(dl-nt-test-set! "not against EDB"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(1). p(2). p(3). r(2).
|
||||
q(X) :- p(X), not(r(X)).")
|
||||
(list (quote q) (quote X)))
|
||||
(list {:X 1} {:X 3}))
|
||||
|
||||
;; Negation against derived relation — needs stratification.
|
||||
(dl-nt-test-set! "not against derived rel"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(1). p(2). p(3). s(2).
|
||||
r(X) :- s(X).
|
||||
q(X) :- p(X), not(r(X)).")
|
||||
(list (quote q) (quote X)))
|
||||
(list {:X 1} {:X 3}))
|
||||
|
||||
;; Two-step strata: r derives via s; q derives via not r.
|
||||
(dl-nt-test-set! "two-step strata"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"node(a). node(b). node(c). node(d).
|
||||
edge(a, b). edge(b, c). edge(c, a).
|
||||
reach(X, Y) :- edge(X, Y).
|
||||
reach(X, Z) :- edge(X, Y), reach(Y, Z).
|
||||
unreachable(X) :- node(X), not(reach(a, X)).")
|
||||
(list (quote unreachable) (quote X)))
|
||||
(list {:X (quote d)}))
|
||||
|
||||
;; Combine negation with arithmetic and comparison.
|
||||
(dl-nt-test-set! "negation with arithmetic"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"n(1). n(2). n(3). n(4). n(5). odd(1). odd(3). odd(5).
|
||||
even(X) :- n(X), not(odd(X)).")
|
||||
(list (quote even) (quote X)))
|
||||
(list {:X 2} {:X 4}))
|
||||
|
||||
;; Empty negation result.
|
||||
(dl-nt-test-set! "negation always succeeds"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(1). p(2). q(X) :- p(X), not(r(X)).")
|
||||
(list (quote q) (quote X)))
|
||||
(list {:X 1} {:X 2}))
|
||||
|
||||
;; Negation always fails.
|
||||
(dl-nt-test-set! "negation always fails"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"p(1). p(2). r(1). r(2). q(X) :- p(X), not(r(X)).")
|
||||
(list (quote q) (quote X)))
|
||||
(list))
|
||||
|
||||
;; Anonymous `_` in a negated literal is existentially quantified
|
||||
;; — it doesn't need to be bound by an earlier body lit. Without
|
||||
;; this exemption the safety check would reject the common idiom
|
||||
;; `orphan(X) :- person(X), not(parent(X, _))`.
|
||||
(dl-nt-test-set! "negation with anonymous var — orphan idiom"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"person(a). person(b). person(c). parent(a, b).
|
||||
orphan(X) :- person(X), not(parent(X, _)).")
|
||||
(list (quote orphan) (quote X)))
|
||||
(list {:X (quote b)} {:X (quote c)}))
|
||||
|
||||
;; Multiple anonymous vars are each independently existential.
|
||||
(dl-nt-test-set! "negation with multiple anonymous vars"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"u(a). u(b). u(c). edge(a, x). edge(b, y).
|
||||
solo(X) :- u(X), not(edge(X, _)).")
|
||||
(list (quote solo) (quote X)))
|
||||
(list {:X (quote c)}))
|
||||
|
||||
;; Stratifiability checks.
|
||||
(dl-nt-test! "non-stratifiable rejected"
|
||||
(dl-nt-throws?
|
||||
(fn ()
|
||||
(let ((db (dl-make-db)))
|
||||
(do
|
||||
(dl-add-rule!
|
||||
db
|
||||
{:head (list (quote p) (quote X))
|
||||
:body (list (list (quote q) (quote X))
|
||||
{:neg (list (quote r) (quote X))})})
|
||||
(dl-add-rule!
|
||||
db
|
||||
{:head (list (quote r) (quote X))
|
||||
:body (list (list (quote p) (quote X)))})
|
||||
(dl-add-fact! db (list (quote q) 1))
|
||||
(dl-saturate! db)))))
|
||||
true)
|
||||
|
||||
(dl-nt-test! "stratifiable accepted"
|
||||
(dl-nt-throws?
|
||||
(fn ()
|
||||
(dl-program
|
||||
"p(1). p(2). r(2).
|
||||
q(X) :- p(X), not(r(X)).")))
|
||||
false)
|
||||
|
||||
;; Multi-stratum chain.
|
||||
(dl-nt-test-set! "three-level strata"
|
||||
(dl-query
|
||||
(dl-program
|
||||
"a(1). a(2). a(3). a(4).
|
||||
b(X) :- a(X), not(c(X)).
|
||||
c(X) :- d(X).
|
||||
d(2).
|
||||
d(4).")
|
||||
(list (quote b) (quote X)))
|
||||
(list {:X 1} {:X 3}))
|
||||
|
||||
;; Safety violation: negation refers to unbound var.
|
||||
(dl-nt-test! "negation safety violation"
|
||||
(dl-nt-throws?
|
||||
(fn ()
|
||||
(dl-program
|
||||
"p(1). q(X) :- p(X), not(r(Y)).")))
|
||||
true))))
|
||||
|
||||
(define
|
||||
dl-negation-tests-run!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(set! dl-nt-pass 0)
|
||||
(set! dl-nt-fail 0)
|
||||
(set! dl-nt-failures (list))
|
||||
(dl-nt-run-all!)
|
||||
{:passed dl-nt-pass
|
||||
:failed dl-nt-fail
|
||||
:total (+ dl-nt-pass dl-nt-fail)
|
||||
:failures dl-nt-failures})))
|
||||
179
lib/datalog/tests/parse.sx
Normal file
179
lib/datalog/tests/parse.sx
Normal file
@@ -0,0 +1,179 @@
|
||||
;; lib/datalog/tests/parse.sx — parser unit tests
|
||||
;;
|
||||
;; Run via: bash lib/datalog/conformance.sh
|
||||
;; Or: (load "lib/datalog/tokenizer.sx") (load "lib/datalog/parser.sx")
|
||||
;; (load "lib/datalog/tests/parse.sx") (dl-parse-tests-run!)
|
||||
|
||||
(define dl-pt-pass 0)
|
||||
(define dl-pt-fail 0)
|
||||
(define dl-pt-failures (list))
|
||||
|
||||
;; Order-independent structural equality. Lists compared positionally,
|
||||
;; dicts as sets of (key, value) pairs. Numbers via = (so 30.0 = 30).
|
||||
(define
|
||||
dl-deep-equal?
|
||||
(fn
|
||||
(a b)
|
||||
(cond
|
||||
((and (list? a) (list? b))
|
||||
(and (= (len a) (len b)) (dl-deep-equal-list? a b 0)))
|
||||
((and (dict? a) (dict? b))
|
||||
(let
|
||||
((ka (keys a)) (kb (keys b)))
|
||||
(and
|
||||
(= (len ka) (len kb))
|
||||
(dl-deep-equal-dict? a b ka 0))))
|
||||
((and (number? a) (number? b)) (= a b))
|
||||
(else (equal? a b)))))
|
||||
|
||||
(define
|
||||
dl-deep-equal-list?
|
||||
(fn
|
||||
(a b i)
|
||||
(cond
|
||||
((>= i (len a)) true)
|
||||
((not (dl-deep-equal? (nth a i) (nth b i))) false)
|
||||
(else (dl-deep-equal-list? a b (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-deep-equal-dict?
|
||||
(fn
|
||||
(a b ka i)
|
||||
(cond
|
||||
((>= i (len ka)) true)
|
||||
((let ((k (nth ka i))) (not (dl-deep-equal? (get a k) (get b k))))
|
||||
false)
|
||||
(else (dl-deep-equal-dict? a b ka (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-pt-test!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-deep-equal? got expected)
|
||||
(set! dl-pt-pass (+ dl-pt-pass 1))
|
||||
(do
|
||||
(set! dl-pt-fail (+ dl-pt-fail 1))
|
||||
(append!
|
||||
dl-pt-failures
|
||||
(str name "\n expected: " expected "\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-pt-throws?
|
||||
(fn
|
||||
(thunk)
|
||||
(let
|
||||
((threw false))
|
||||
(do (guard (e (#t (set! threw true))) (thunk)) threw))))
|
||||
|
||||
(define
|
||||
dl-pt-run-all!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(dl-pt-test! "empty program" (dl-parse "") (list))
|
||||
(dl-pt-test! "fact" (dl-parse "parent(tom, bob).") (list {:body (list) :head (list (quote parent) (quote tom) (quote bob))}))
|
||||
(dl-pt-test!
|
||||
"two facts"
|
||||
(dl-parse "parent(tom, bob). parent(bob, ann).")
|
||||
(list {:body (list) :head (list (quote parent) (quote tom) (quote bob))} {:body (list) :head (list (quote parent) (quote bob) (quote ann))}))
|
||||
(dl-pt-test! "zero-ary fact" (dl-parse "ready.") (list {:body (list) :head (list (quote ready))}))
|
||||
(dl-pt-test!
|
||||
"rule one body lit"
|
||||
(dl-parse "ancestor(X, Y) :- parent(X, Y).")
|
||||
(list {:body (list (list (quote parent) (quote X) (quote Y))) :head (list (quote ancestor) (quote X) (quote Y))}))
|
||||
(dl-pt-test!
|
||||
"recursive rule"
|
||||
(dl-parse "ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")
|
||||
(list {:body (list (list (quote parent) (quote X) (quote Y)) (list (quote ancestor) (quote Y) (quote Z))) :head (list (quote ancestor) (quote X) (quote Z))}))
|
||||
(dl-pt-test!
|
||||
"query single"
|
||||
(dl-parse "?- ancestor(tom, X).")
|
||||
(list {:query (list (list (quote ancestor) (quote tom) (quote X)))}))
|
||||
(dl-pt-test!
|
||||
"query multi"
|
||||
(dl-parse "?- p(X), q(X).")
|
||||
(list {:query (list (list (quote p) (quote X)) (list (quote q) (quote X)))}))
|
||||
(dl-pt-test!
|
||||
"negation"
|
||||
(dl-parse "safe(X) :- person(X), not(parent(X, _)).")
|
||||
(list {:body (list (list (quote person) (quote X)) {:neg (list (quote parent) (quote X) (quote _))}) :head (list (quote safe) (quote X))}))
|
||||
(dl-pt-test!
|
||||
"number arg"
|
||||
(dl-parse "age(alice, 30).")
|
||||
(list {:body (list) :head (list (quote age) (quote alice) 30)}))
|
||||
(dl-pt-test!
|
||||
"string arg"
|
||||
(dl-parse "label(x, \"hi\").")
|
||||
(list {:body (list) :head (list (quote label) (quote x) "hi")}))
|
||||
;; Quoted 'atoms' parse as strings — a uppercase-starting name
|
||||
;; in quotes used to misclassify as a variable and reject the
|
||||
;; fact as non-ground.
|
||||
(dl-pt-test!
|
||||
"quoted atom arg parses as string"
|
||||
(dl-parse "p('Hello World').")
|
||||
(list {:body (list) :head (list (quote p) "Hello World")}))
|
||||
(dl-pt-test!
|
||||
"comparison literal"
|
||||
(dl-parse "p(X) :- <(X, 5).")
|
||||
(list {:body (list (list (string->symbol "<") (quote X) 5)) :head (list (quote p) (quote X))}))
|
||||
(dl-pt-test!
|
||||
"is with arith"
|
||||
(dl-parse "succ(X, Y) :- nat(X), is(Y, +(X, 1)).")
|
||||
(list {:body (list (list (quote nat) (quote X)) (list (quote is) (quote Y) (list (string->symbol "+") (quote X) 1))) :head (list (quote succ) (quote X) (quote Y))}))
|
||||
(dl-pt-test!
|
||||
"mixed program"
|
||||
(dl-parse "p(a). p(b). q(X) :- p(X). ?- q(Y).")
|
||||
(list {:body (list) :head (list (quote p) (quote a))} {:body (list) :head (list (quote p) (quote b))} {:body (list (list (quote p) (quote X))) :head (list (quote q) (quote X))} {:query (list (list (quote q) (quote Y)))}))
|
||||
(dl-pt-test!
|
||||
"comments skipped"
|
||||
(dl-parse "% comment\nfoo(a).\n/* block */ bar(b).")
|
||||
(list {:body (list) :head (list (quote foo) (quote a))} {:body (list) :head (list (quote bar) (quote b))}))
|
||||
(dl-pt-test!
|
||||
"underscore var"
|
||||
(dl-parse "p(X) :- q(X, _).")
|
||||
(list {:body (list (list (quote q) (quote X) (quote _))) :head (list (quote p) (quote X))}))
|
||||
;; Negative number literals parse as one negative number,
|
||||
;; while subtraction (`-(X, Y)`) compound is preserved.
|
||||
(dl-pt-test!
|
||||
"negative integer literal"
|
||||
(dl-parse "n(-3).")
|
||||
(list {:head (list (quote n) -3) :body (list)}))
|
||||
|
||||
(dl-pt-test!
|
||||
"subtraction compound preserved"
|
||||
(dl-parse "r(X) :- is(X, -(10, 3)).")
|
||||
(list
|
||||
{:head (list (quote r) (quote X))
|
||||
:body (list (list (quote is) (quote X)
|
||||
(list (string->symbol "-") 10 3)))}))
|
||||
|
||||
(dl-pt-test!
|
||||
"number as relation name raises"
|
||||
(dl-pt-throws? (fn () (dl-parse "1(X) :- p(X).")))
|
||||
true)
|
||||
|
||||
(dl-pt-test!
|
||||
"var as relation name raises"
|
||||
(dl-pt-throws? (fn () (dl-parse "P(X).")))
|
||||
true)
|
||||
|
||||
(dl-pt-test!
|
||||
"missing dot raises"
|
||||
(dl-pt-throws? (fn () (dl-parse "p(a)")))
|
||||
true)
|
||||
(dl-pt-test!
|
||||
"trailing comma raises"
|
||||
(dl-pt-throws? (fn () (dl-parse "p(a,).")))
|
||||
true))))
|
||||
|
||||
(define
|
||||
dl-parse-tests-run!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(set! dl-pt-pass 0)
|
||||
(set! dl-pt-fail 0)
|
||||
(set! dl-pt-failures (list))
|
||||
(dl-pt-run-all!)
|
||||
{:failures dl-pt-failures :total (+ dl-pt-pass dl-pt-fail) :passed dl-pt-pass :failed dl-pt-fail})))
|
||||
153
lib/datalog/tests/semi_naive.sx
Normal file
153
lib/datalog/tests/semi_naive.sx
Normal file
@@ -0,0 +1,153 @@
|
||||
;; lib/datalog/tests/semi_naive.sx — semi-naive correctness vs naive.
|
||||
;;
|
||||
;; Strategy: differential — run both saturators on each program and
|
||||
;; compare the resulting per-relation tuple counts. Counting (not
|
||||
;; element-wise set equality) keeps the suite fast under the bundled
|
||||
;; conformance session; correctness on the inhabitants is covered by
|
||||
;; eval.sx and builtins.sx (which use dl-saturate! by default — the
|
||||
;; semi-naive saturator).
|
||||
|
||||
(define dl-sn-pass 0)
|
||||
(define dl-sn-fail 0)
|
||||
(define dl-sn-failures (list))
|
||||
|
||||
(define
|
||||
dl-sn-test!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(equal? got expected)
|
||||
(set! dl-sn-pass (+ dl-sn-pass 1))
|
||||
(do
|
||||
(set! dl-sn-fail (+ dl-sn-fail 1))
|
||||
(append!
|
||||
dl-sn-failures
|
||||
(str name "\n expected: " expected "\n got: " got))))))
|
||||
|
||||
;; Load `source` into both a semi-naive and a naive db and return a
|
||||
;; list of (rel-name semi-count naive-count) triples. Both sets must
|
||||
;; have the same union of relation names.
|
||||
(define
|
||||
dl-sn-counts
|
||||
(fn
|
||||
(source)
|
||||
(let
|
||||
((db-s (dl-program source)) (db-n (dl-program source)))
|
||||
(do
|
||||
(dl-saturate! db-s)
|
||||
(dl-saturate-naive! db-n)
|
||||
(let
|
||||
((out (list)))
|
||||
(do
|
||||
(for-each
|
||||
(fn
|
||||
(k)
|
||||
(append!
|
||||
out
|
||||
(list
|
||||
k
|
||||
(len (dl-relation db-s k))
|
||||
(len (dl-relation db-n k)))))
|
||||
(keys (get db-s :facts)))
|
||||
out))))))
|
||||
|
||||
(define
|
||||
dl-sn-counts-agree?
|
||||
(fn
|
||||
(counts)
|
||||
(cond
|
||||
((= (len counts) 0) true)
|
||||
(else
|
||||
(let
|
||||
((row (first counts)))
|
||||
(and
|
||||
(= (nth row 1) (nth row 2))
|
||||
(dl-sn-counts-agree? (rest counts))))))))
|
||||
|
||||
(define
|
||||
dl-sn-chain-source
|
||||
(fn
|
||||
(n)
|
||||
(let
|
||||
((parts (list "")))
|
||||
(do
|
||||
(define
|
||||
dl-sn-loop
|
||||
(fn
|
||||
(i)
|
||||
(when
|
||||
(< i n)
|
||||
(do
|
||||
(append! parts (str "parent(" i ", " (+ i 1) "). "))
|
||||
(dl-sn-loop (+ i 1))))))
|
||||
(dl-sn-loop 0)
|
||||
(str
|
||||
(join "" parts)
|
||||
"ancestor(X, Y) :- parent(X, Y). "
|
||||
"ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")))))
|
||||
|
||||
(define
|
||||
dl-sn-run-all!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(dl-sn-test!
|
||||
"ancestor closure counts match"
|
||||
(dl-sn-counts-agree?
|
||||
(dl-sn-counts
|
||||
"parent(a, b). parent(b, c). parent(c, d).\n ancestor(X, Y) :- parent(X, Y).\n ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z)."))
|
||||
true)
|
||||
(dl-sn-test!
|
||||
"cyclic reach counts match"
|
||||
(dl-sn-counts-agree?
|
||||
(dl-sn-counts
|
||||
"edge(1, 2). edge(2, 3). edge(3, 1). edge(3, 4).\n reach(X, Y) :- edge(X, Y).\n reach(X, Z) :- edge(X, Y), reach(Y, Z)."))
|
||||
true)
|
||||
(dl-sn-test!
|
||||
"same-gen counts match"
|
||||
(dl-sn-counts-agree?
|
||||
(dl-sn-counts
|
||||
"parent(a, b). parent(a, c). parent(b, d). parent(c, e).\n person(a). person(b). person(c). person(d). person(e).\n sg(X, X) :- person(X).\n sg(X, Y) :- parent(P1, X), sg(P1, P2), parent(P2, Y)."))
|
||||
true)
|
||||
(dl-sn-test!
|
||||
"rules with builtins counts match"
|
||||
(dl-sn-counts-agree?
|
||||
(dl-sn-counts
|
||||
"n(1). n(2). n(3). n(4). n(5).\n small(X) :- n(X), <(X, 5).\n succ(X, Y) :- n(X), <(X, 5), is(Y, +(X, 1))."))
|
||||
true)
|
||||
(dl-sn-test!
|
||||
"static rule fires under semi-naive"
|
||||
(dl-sn-counts-agree?
|
||||
(dl-sn-counts "p(a). p(b). q(X) :- p(X), =(X, a)."))
|
||||
true)
|
||||
;; Chain length 12 — multiple semi-naive iterations against
|
||||
;; the recursive ancestor rule (differential vs naive).
|
||||
(dl-sn-test!
|
||||
"chain-12 ancestor counts match"
|
||||
(dl-sn-counts-agree? (dl-sn-counts (dl-sn-chain-source 12)))
|
||||
true)
|
||||
;; Chain length 25 — semi-naive only — first-arg index makes
|
||||
;; this tractable in conformance budget.
|
||||
(dl-sn-test!
|
||||
"chain-25 ancestor count value (semi only)"
|
||||
(let
|
||||
((db (dl-program (dl-sn-chain-source 25))))
|
||||
(do (dl-saturate! db) (len (dl-relation db "ancestor"))))
|
||||
325)
|
||||
(dl-sn-test!
|
||||
"query through semi saturate"
|
||||
(let
|
||||
((db (dl-program "parent(a, b). parent(b, c).\n ancestor(X, Y) :- parent(X, Y).\n ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z).")))
|
||||
(len (dl-query db (list (quote ancestor) (quote a) (quote X)))))
|
||||
2))))
|
||||
|
||||
(define
|
||||
dl-semi-naive-tests-run!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(set! dl-sn-pass 0)
|
||||
(set! dl-sn-fail 0)
|
||||
(set! dl-sn-failures (list))
|
||||
(dl-sn-run-all!)
|
||||
{:failures dl-sn-failures :total (+ dl-sn-pass dl-sn-fail) :passed dl-sn-pass :failed dl-sn-fail})))
|
||||
189
lib/datalog/tests/tokenize.sx
Normal file
189
lib/datalog/tests/tokenize.sx
Normal file
@@ -0,0 +1,189 @@
|
||||
;; lib/datalog/tests/tokenize.sx — tokenizer unit tests
|
||||
;;
|
||||
;; Run via: bash lib/datalog/conformance.sh
|
||||
;; Or: (load "lib/datalog/tokenizer.sx") (load "lib/datalog/tests/tokenize.sx")
|
||||
;; (dl-tokenize-tests-run!)
|
||||
|
||||
(define dl-tk-pass 0)
|
||||
(define dl-tk-fail 0)
|
||||
(define dl-tk-failures (list))
|
||||
|
||||
(define
|
||||
dl-tk-test!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(= got expected)
|
||||
(set! dl-tk-pass (+ dl-tk-pass 1))
|
||||
(do
|
||||
(set! dl-tk-fail (+ dl-tk-fail 1))
|
||||
(append!
|
||||
dl-tk-failures
|
||||
(str name "\n expected: " expected "\n got: " got))))))
|
||||
|
||||
(define dl-tk-types (fn (toks) (map (fn (t) (get t :type)) toks)))
|
||||
(define dl-tk-values (fn (toks) (map (fn (t) (get t :value)) toks)))
|
||||
|
||||
(define
|
||||
dl-tk-run-all!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(dl-tk-test! "empty" (dl-tk-types (dl-tokenize "")) (list "eof"))
|
||||
(dl-tk-test!
|
||||
"atom dot"
|
||||
(dl-tk-types (dl-tokenize "foo."))
|
||||
(list "atom" "punct" "eof"))
|
||||
(dl-tk-test!
|
||||
"atom dot value"
|
||||
(dl-tk-values (dl-tokenize "foo."))
|
||||
(list "foo" "." nil))
|
||||
(dl-tk-test!
|
||||
"var"
|
||||
(dl-tk-types (dl-tokenize "X."))
|
||||
(list "var" "punct" "eof"))
|
||||
(dl-tk-test!
|
||||
"underscore var"
|
||||
(dl-tk-types (dl-tokenize "_x."))
|
||||
(list "var" "punct" "eof"))
|
||||
(dl-tk-test!
|
||||
"integer"
|
||||
(dl-tk-values (dl-tokenize "42"))
|
||||
(list 42 nil))
|
||||
(dl-tk-test!
|
||||
"decimal"
|
||||
(dl-tk-values (dl-tokenize "3.14"))
|
||||
(list 3.14 nil))
|
||||
(dl-tk-test!
|
||||
"string"
|
||||
(dl-tk-values (dl-tokenize "\"hello\""))
|
||||
(list "hello" nil))
|
||||
;; Quoted 'atoms' tokenize as strings — see the type-table
|
||||
;; comment in lib/datalog/tokenizer.sx for the rationale.
|
||||
(dl-tk-test!
|
||||
"quoted atom as string"
|
||||
(dl-tk-types (dl-tokenize "'two words'"))
|
||||
(list "string" "eof"))
|
||||
(dl-tk-test!
|
||||
"quoted atom value"
|
||||
(dl-tk-values (dl-tokenize "'two words'"))
|
||||
(list "two words" nil))
|
||||
;; A quoted atom whose name would otherwise be a variable
|
||||
;; (uppercase / leading underscore) is now safely a string —
|
||||
;; this was the bug that motivated the type change.
|
||||
(dl-tk-test!
|
||||
"quoted Uppercase as string"
|
||||
(dl-tk-types (dl-tokenize "'Hello'"))
|
||||
(list "string" "eof"))
|
||||
(dl-tk-test! ":-" (dl-tk-values (dl-tokenize ":-")) (list ":-" nil))
|
||||
(dl-tk-test! "?-" (dl-tk-values (dl-tokenize "?-")) (list "?-" nil))
|
||||
(dl-tk-test! "<=" (dl-tk-values (dl-tokenize "<=")) (list "<=" nil))
|
||||
(dl-tk-test! ">=" (dl-tk-values (dl-tokenize ">=")) (list ">=" nil))
|
||||
(dl-tk-test! "!=" (dl-tk-values (dl-tokenize "!=")) (list "!=" nil))
|
||||
(dl-tk-test!
|
||||
"single op values"
|
||||
(dl-tk-values (dl-tokenize "< > = + - * /"))
|
||||
(list "<" ">" "=" "+" "-" "*" "/" nil))
|
||||
(dl-tk-test!
|
||||
"single op types"
|
||||
(dl-tk-types (dl-tokenize "< > = + - * /"))
|
||||
(list "op" "op" "op" "op" "op" "op" "op" "eof"))
|
||||
(dl-tk-test!
|
||||
"punct"
|
||||
(dl-tk-values (dl-tokenize "( ) , ."))
|
||||
(list "(" ")" "," "." nil))
|
||||
(dl-tk-test!
|
||||
"fact tokens"
|
||||
(dl-tk-types (dl-tokenize "parent(tom, bob)."))
|
||||
(list "atom" "punct" "atom" "punct" "atom" "punct" "punct" "eof"))
|
||||
(dl-tk-test!
|
||||
"rule shape"
|
||||
(dl-tk-types (dl-tokenize "p(X) :- q(X)."))
|
||||
(list
|
||||
"atom"
|
||||
"punct"
|
||||
"var"
|
||||
"punct"
|
||||
"op"
|
||||
"atom"
|
||||
"punct"
|
||||
"var"
|
||||
"punct"
|
||||
"punct"
|
||||
"eof"))
|
||||
(dl-tk-test!
|
||||
"comparison literal"
|
||||
(dl-tk-values (dl-tokenize "<(X, 5)"))
|
||||
(list "<" "(" "X" "," 5 ")" nil))
|
||||
(dl-tk-test!
|
||||
"is form"
|
||||
(dl-tk-values (dl-tokenize "is(Y, +(X, 1))"))
|
||||
(list "is" "(" "Y" "," "+" "(" "X" "," 1 ")" ")" nil))
|
||||
(dl-tk-test!
|
||||
"line comment"
|
||||
(dl-tk-types (dl-tokenize "% comment line\nfoo."))
|
||||
(list "atom" "punct" "eof"))
|
||||
(dl-tk-test!
|
||||
"block comment"
|
||||
(dl-tk-types (dl-tokenize "/* a\nb */ x."))
|
||||
(list "atom" "punct" "eof"))
|
||||
;; Unexpected characters surface at tokenize time rather
|
||||
;; than being silently consumed (previously `?(X)` parsed as
|
||||
;; if the leading `?` weren't there).
|
||||
(dl-tk-test!
|
||||
"unexpected char raises"
|
||||
(let ((threw false))
|
||||
(do
|
||||
(guard (e (#t (set! threw true)))
|
||||
(dl-tokenize "?(X)"))
|
||||
threw))
|
||||
true)
|
||||
|
||||
;; Unterminated string / quoted-atom must raise.
|
||||
(dl-tk-test!
|
||||
"unterminated string raises"
|
||||
(let ((threw false))
|
||||
(do
|
||||
(guard (e (#t (set! threw true)))
|
||||
(dl-tokenize "\"unclosed"))
|
||||
threw))
|
||||
true)
|
||||
|
||||
(dl-tk-test!
|
||||
"unterminated quoted atom raises"
|
||||
(let ((threw false))
|
||||
(do
|
||||
(guard (e (#t (set! threw true)))
|
||||
(dl-tokenize "'unclosed"))
|
||||
threw))
|
||||
true)
|
||||
|
||||
;; Unterminated block comment must raise — previously it was
|
||||
;; silently consumed to EOF.
|
||||
(dl-tk-test!
|
||||
"unterminated block comment raises"
|
||||
(let ((threw false))
|
||||
(do
|
||||
(guard (e (#t (set! threw true)))
|
||||
(dl-tokenize "/* unclosed comment"))
|
||||
threw))
|
||||
true)
|
||||
(dl-tk-test!
|
||||
"whitespace"
|
||||
(dl-tk-types (dl-tokenize " foo ,\t bar ."))
|
||||
(list "atom" "punct" "atom" "punct" "eof"))
|
||||
(dl-tk-test!
|
||||
"positions"
|
||||
(map (fn (t) (get t :pos)) (dl-tokenize "foo bar"))
|
||||
(list 0 4 7)))))
|
||||
|
||||
(define
|
||||
dl-tokenize-tests-run!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(set! dl-tk-pass 0)
|
||||
(set! dl-tk-fail 0)
|
||||
(set! dl-tk-failures (list))
|
||||
(dl-tk-run-all!)
|
||||
{:failures dl-tk-failures :total (+ dl-tk-pass dl-tk-fail) :passed dl-tk-pass :failed dl-tk-fail})))
|
||||
194
lib/datalog/tests/unify.sx
Normal file
194
lib/datalog/tests/unify.sx
Normal file
@@ -0,0 +1,194 @@
|
||||
;; lib/datalog/tests/unify.sx — unification + substitution tests.
|
||||
|
||||
(define dl-ut-pass 0)
|
||||
(define dl-ut-fail 0)
|
||||
(define dl-ut-failures (list))
|
||||
|
||||
(define
|
||||
dl-ut-deep-equal?
|
||||
(fn
|
||||
(a b)
|
||||
(cond
|
||||
((and (list? a) (list? b))
|
||||
(and (= (len a) (len b)) (dl-ut-deq-list? a b 0)))
|
||||
((and (dict? a) (dict? b))
|
||||
(let
|
||||
((ka (keys a)) (kb (keys b)))
|
||||
(and (= (len ka) (len kb)) (dl-ut-deq-dict? a b ka 0))))
|
||||
((and (number? a) (number? b)) (= a b))
|
||||
(else (equal? a b)))))
|
||||
|
||||
(define
|
||||
dl-ut-deq-list?
|
||||
(fn
|
||||
(a b i)
|
||||
(cond
|
||||
((>= i (len a)) true)
|
||||
((not (dl-ut-deep-equal? (nth a i) (nth b i))) false)
|
||||
(else (dl-ut-deq-list? a b (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-ut-deq-dict?
|
||||
(fn
|
||||
(a b ka i)
|
||||
(cond
|
||||
((>= i (len ka)) true)
|
||||
((let ((k (nth ka i))) (not (dl-ut-deep-equal? (get a k) (get b k))))
|
||||
false)
|
||||
(else (dl-ut-deq-dict? a b ka (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-ut-test!
|
||||
(fn
|
||||
(name got expected)
|
||||
(if
|
||||
(dl-ut-deep-equal? got expected)
|
||||
(set! dl-ut-pass (+ dl-ut-pass 1))
|
||||
(do
|
||||
(set! dl-ut-fail (+ dl-ut-fail 1))
|
||||
(append!
|
||||
dl-ut-failures
|
||||
(str name "\n expected: " expected "\n got: " got))))))
|
||||
|
||||
(define
|
||||
dl-ut-run-all!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(dl-ut-test! "var? uppercase" (dl-var? (quote X)) true)
|
||||
(dl-ut-test! "var? underscore" (dl-var? (quote _foo)) true)
|
||||
(dl-ut-test! "var? lowercase" (dl-var? (quote tom)) false)
|
||||
(dl-ut-test! "var? number" (dl-var? 5) false)
|
||||
(dl-ut-test! "var? string" (dl-var? "hi") false)
|
||||
(dl-ut-test! "var? list" (dl-var? (list 1)) false)
|
||||
(dl-ut-test!
|
||||
"atom-atom match"
|
||||
(dl-unify (quote tom) (quote tom) (dl-empty-subst))
|
||||
{})
|
||||
(dl-ut-test!
|
||||
"atom-atom fail"
|
||||
(dl-unify (quote tom) (quote bob) (dl-empty-subst))
|
||||
nil)
|
||||
(dl-ut-test!
|
||||
"num-num match"
|
||||
(dl-unify 5 5 (dl-empty-subst))
|
||||
{})
|
||||
(dl-ut-test!
|
||||
"num-num fail"
|
||||
(dl-unify 5 6 (dl-empty-subst))
|
||||
nil)
|
||||
(dl-ut-test!
|
||||
"string match"
|
||||
(dl-unify "hi" "hi" (dl-empty-subst))
|
||||
{})
|
||||
(dl-ut-test! "string fail" (dl-unify "hi" "bye" (dl-empty-subst)) nil)
|
||||
(dl-ut-test!
|
||||
"var-atom binds"
|
||||
(dl-unify (quote X) (quote tom) (dl-empty-subst))
|
||||
{:X (quote tom)})
|
||||
(dl-ut-test!
|
||||
"atom-var binds"
|
||||
(dl-unify (quote tom) (quote X) (dl-empty-subst))
|
||||
{:X (quote tom)})
|
||||
(dl-ut-test!
|
||||
"var-var same"
|
||||
(dl-unify (quote X) (quote X) (dl-empty-subst))
|
||||
{})
|
||||
(dl-ut-test!
|
||||
"var-var bind"
|
||||
(let
|
||||
((s (dl-unify (quote X) (quote Y) (dl-empty-subst))))
|
||||
(dl-walk (quote X) s))
|
||||
(quote Y))
|
||||
(dl-ut-test!
|
||||
"tuple match"
|
||||
(dl-unify
|
||||
(list (quote parent) (quote X) (quote bob))
|
||||
(list (quote parent) (quote tom) (quote Y))
|
||||
(dl-empty-subst))
|
||||
{:X (quote tom) :Y (quote bob)})
|
||||
(dl-ut-test!
|
||||
"tuple arity mismatch"
|
||||
(dl-unify
|
||||
(list (quote p) (quote X))
|
||||
(list (quote p) (quote a) (quote b))
|
||||
(dl-empty-subst))
|
||||
nil)
|
||||
(dl-ut-test!
|
||||
"tuple head mismatch"
|
||||
(dl-unify
|
||||
(list (quote p) (quote X))
|
||||
(list (quote q) (quote X))
|
||||
(dl-empty-subst))
|
||||
nil)
|
||||
(dl-ut-test!
|
||||
"walk chain"
|
||||
(let
|
||||
((s1 (dl-unify (quote X) (quote Y) (dl-empty-subst))))
|
||||
(let
|
||||
((s2 (dl-unify (quote Y) (quote tom) s1)))
|
||||
(dl-walk (quote X) s2)))
|
||||
(quote tom))
|
||||
|
||||
;; Walk with circular substitution must not infinite-loop.
|
||||
;; Cycles return the current term unchanged.
|
||||
(dl-ut-test!
|
||||
"walk circular subst no hang"
|
||||
(let ((s (dl-bind (quote B) (quote A)
|
||||
(dl-bind (quote A) (quote B) (dl-empty-subst)))))
|
||||
(dl-walk (quote A) s))
|
||||
(quote A))
|
||||
(dl-ut-test!
|
||||
"apply subst on tuple"
|
||||
(let
|
||||
((s (dl-bind (quote X) (quote tom) (dl-empty-subst))))
|
||||
(dl-apply-subst (list (quote parent) (quote X) (quote Y)) s))
|
||||
(list (quote parent) (quote tom) (quote Y)))
|
||||
(dl-ut-test!
|
||||
"ground? all const"
|
||||
(dl-ground?
|
||||
(list (quote p) (quote tom) 5)
|
||||
(dl-empty-subst))
|
||||
true)
|
||||
(dl-ut-test!
|
||||
"ground? unbound var"
|
||||
(dl-ground? (list (quote p) (quote X)) (dl-empty-subst))
|
||||
false)
|
||||
(dl-ut-test!
|
||||
"ground? bound var"
|
||||
(let
|
||||
((s (dl-bind (quote X) (quote tom) (dl-empty-subst))))
|
||||
(dl-ground? (list (quote p) (quote X)) s))
|
||||
true)
|
||||
(dl-ut-test!
|
||||
"ground? bare var"
|
||||
(dl-ground? (quote X) (dl-empty-subst))
|
||||
false)
|
||||
(dl-ut-test!
|
||||
"vars-of basic"
|
||||
(dl-vars-of
|
||||
(list (quote p) (quote X) (quote tom) (quote Y) (quote X)))
|
||||
(list "X" "Y"))
|
||||
(dl-ut-test!
|
||||
"vars-of ground"
|
||||
(dl-vars-of (list (quote p) (quote tom) (quote bob)))
|
||||
(list))
|
||||
(dl-ut-test!
|
||||
"vars-of nested compound"
|
||||
(dl-vars-of
|
||||
(list
|
||||
(quote is)
|
||||
(quote Z)
|
||||
(list (string->symbol "+") (quote X) 1)))
|
||||
(list "Z" "X")))))
|
||||
|
||||
(define
|
||||
dl-unify-tests-run!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(set! dl-ut-pass 0)
|
||||
(set! dl-ut-fail 0)
|
||||
(set! dl-ut-failures (list))
|
||||
(dl-ut-run-all!)
|
||||
{:failures dl-ut-failures :total (+ dl-ut-pass dl-ut-fail) :passed dl-ut-pass :failed dl-ut-fail})))
|
||||
269
lib/datalog/tokenizer.sx
Normal file
269
lib/datalog/tokenizer.sx
Normal file
@@ -0,0 +1,269 @@
|
||||
;; lib/datalog/tokenizer.sx — Datalog source → token stream
|
||||
;;
|
||||
;; Tokens: {:type T :value V :pos P}
|
||||
;; Types:
|
||||
;; "atom" — lowercase-start bare identifier
|
||||
;; "var" — uppercase-start or _-start ident (value is the name)
|
||||
;; "number" — numeric literal (decoded to number)
|
||||
;; "string" — "..." string literal OR quoted 'atom' (treated as a
|
||||
;; string value to avoid the var-vs-atom ambiguity that
|
||||
;; would arise from a quoted atom whose name starts with
|
||||
;; an uppercase letter or underscore)
|
||||
;; "punct" — ( ) , .
|
||||
;; "op" — :- ?- <= >= != < > = + - * /
|
||||
;; "eof"
|
||||
;;
|
||||
;; Datalog has no function symbols in arg position; the parser still
|
||||
;; accepts nested compounds for arithmetic ((is X (+ A B))) but safety
|
||||
;; analysis rejects non-arithmetic nesting at rule-load time.
|
||||
|
||||
(define dl-make-token (fn (type value pos) {:type type :value value :pos pos}))
|
||||
|
||||
(define dl-digit? (fn (c) (and (>= c "0") (<= c "9"))))
|
||||
(define dl-lower? (fn (c) (and (>= c "a") (<= c "z"))))
|
||||
(define dl-upper? (fn (c) (and (>= c "A") (<= c "Z"))))
|
||||
|
||||
(define
|
||||
dl-ident-char?
|
||||
(fn (c) (or (dl-lower? c) (dl-upper? c) (dl-digit? c) (= c "_"))))
|
||||
|
||||
(define dl-ws? (fn (c) (or (= c " ") (= c "\t") (= c "\n") (= c "\r"))))
|
||||
|
||||
(define
|
||||
dl-tokenize
|
||||
(fn
|
||||
(src)
|
||||
(let
|
||||
((tokens (list)) (pos 0) (src-len (len src)))
|
||||
(define
|
||||
dl-peek
|
||||
(fn
|
||||
(offset)
|
||||
(if (< (+ pos offset) src-len) (nth src (+ pos offset)) nil)))
|
||||
(define cur (fn () (dl-peek 0)))
|
||||
(define advance! (fn (n) (set! pos (+ pos n))))
|
||||
(define
|
||||
at?
|
||||
(fn
|
||||
(s)
|
||||
(let
|
||||
((sl (len s)))
|
||||
(and (<= (+ pos sl) src-len) (= (slice src pos (+ pos sl)) s)))))
|
||||
(define
|
||||
dl-emit!
|
||||
(fn
|
||||
(type value start)
|
||||
(append! tokens (dl-make-token type value start))))
|
||||
(define
|
||||
skip-line-comment!
|
||||
(fn
|
||||
()
|
||||
(when
|
||||
(and (< pos src-len) (not (= (cur) "\n")))
|
||||
(do (advance! 1) (skip-line-comment!)))))
|
||||
(define
|
||||
skip-block-comment!
|
||||
(fn
|
||||
()
|
||||
(cond
|
||||
((>= pos src-len)
|
||||
(error (str "Tokenizer: unterminated block comment "
|
||||
"(started at position " pos ")")))
|
||||
((and (= (cur) "*") (< (+ pos 1) src-len) (= (dl-peek 1) "/"))
|
||||
(advance! 2))
|
||||
(else (do (advance! 1) (skip-block-comment!))))))
|
||||
(define
|
||||
skip-ws!
|
||||
(fn
|
||||
()
|
||||
(cond
|
||||
((>= pos src-len) nil)
|
||||
((dl-ws? (cur)) (do (advance! 1) (skip-ws!)))
|
||||
((= (cur) "%")
|
||||
(do (advance! 1) (skip-line-comment!) (skip-ws!)))
|
||||
((and (= (cur) "/") (< (+ pos 1) src-len) (= (dl-peek 1) "*"))
|
||||
(do (advance! 2) (skip-block-comment!) (skip-ws!)))
|
||||
(else nil))))
|
||||
(define
|
||||
read-ident
|
||||
(fn
|
||||
(start)
|
||||
(do
|
||||
(when
|
||||
(and (< pos src-len) (dl-ident-char? (cur)))
|
||||
(do (advance! 1) (read-ident start)))
|
||||
(slice src start pos))))
|
||||
(define
|
||||
read-decimal-digits!
|
||||
(fn
|
||||
()
|
||||
(when
|
||||
(and (< pos src-len) (dl-digit? (cur)))
|
||||
(do (advance! 1) (read-decimal-digits!)))))
|
||||
(define
|
||||
read-number
|
||||
(fn
|
||||
(start)
|
||||
(do
|
||||
(read-decimal-digits!)
|
||||
(when
|
||||
(and
|
||||
(< pos src-len)
|
||||
(= (cur) ".")
|
||||
(< (+ pos 1) src-len)
|
||||
(dl-digit? (dl-peek 1)))
|
||||
(do (advance! 1) (read-decimal-digits!)))
|
||||
(parse-number (slice src start pos)))))
|
||||
(define
|
||||
read-quoted
|
||||
(fn
|
||||
(quote-char)
|
||||
(let
|
||||
((chars (list)))
|
||||
(advance! 1)
|
||||
(define
|
||||
loop
|
||||
(fn
|
||||
()
|
||||
(cond
|
||||
((>= pos src-len)
|
||||
(error
|
||||
(str "Tokenizer: unterminated "
|
||||
(if (= quote-char "'") "quoted atom" "string")
|
||||
" (started near position " pos ")")))
|
||||
((= (cur) "\\")
|
||||
(do
|
||||
(advance! 1)
|
||||
(when
|
||||
(< pos src-len)
|
||||
(let
|
||||
((ch (cur)))
|
||||
(do
|
||||
(cond
|
||||
((= ch "n") (append! chars "\n"))
|
||||
((= ch "t") (append! chars "\t"))
|
||||
((= ch "r") (append! chars "\r"))
|
||||
((= ch "\\") (append! chars "\\"))
|
||||
((= ch "'") (append! chars "'"))
|
||||
((= ch "\"") (append! chars "\""))
|
||||
(else (append! chars ch)))
|
||||
(advance! 1))))
|
||||
(loop)))
|
||||
((= (cur) quote-char) (advance! 1))
|
||||
(else
|
||||
(do (append! chars (cur)) (advance! 1) (loop))))))
|
||||
(loop)
|
||||
(join "" chars))))
|
||||
(define
|
||||
scan!
|
||||
(fn
|
||||
()
|
||||
(do
|
||||
(skip-ws!)
|
||||
(when
|
||||
(< pos src-len)
|
||||
(let
|
||||
((ch (cur)) (start pos))
|
||||
(cond
|
||||
((at? ":-")
|
||||
(do
|
||||
(dl-emit! "op" ":-" start)
|
||||
(advance! 2)
|
||||
(scan!)))
|
||||
((at? "?-")
|
||||
(do
|
||||
(dl-emit! "op" "?-" start)
|
||||
(advance! 2)
|
||||
(scan!)))
|
||||
((at? "<=")
|
||||
(do
|
||||
(dl-emit! "op" "<=" start)
|
||||
(advance! 2)
|
||||
(scan!)))
|
||||
((at? ">=")
|
||||
(do
|
||||
(dl-emit! "op" ">=" start)
|
||||
(advance! 2)
|
||||
(scan!)))
|
||||
((at? "!=")
|
||||
(do
|
||||
(dl-emit! "op" "!=" start)
|
||||
(advance! 2)
|
||||
(scan!)))
|
||||
((dl-digit? ch)
|
||||
(do
|
||||
(dl-emit! "number" (read-number start) start)
|
||||
(scan!)))
|
||||
((= ch "'")
|
||||
;; Quoted 'atoms' tokenize as strings so a name
|
||||
;; like 'Hello World' doesn't get misclassified
|
||||
;; as a variable by dl-var? (which inspects the
|
||||
;; symbol's first character).
|
||||
(do (dl-emit! "string" (read-quoted "'") start) (scan!)))
|
||||
((= ch "\"")
|
||||
(do (dl-emit! "string" (read-quoted "\"") start) (scan!)))
|
||||
((dl-lower? ch)
|
||||
(do (dl-emit! "atom" (read-ident start) start) (scan!)))
|
||||
((or (dl-upper? ch) (= ch "_"))
|
||||
(do (dl-emit! "var" (read-ident start) start) (scan!)))
|
||||
((= ch "(")
|
||||
(do
|
||||
(dl-emit! "punct" "(" start)
|
||||
(advance! 1)
|
||||
(scan!)))
|
||||
((= ch ")")
|
||||
(do
|
||||
(dl-emit! "punct" ")" start)
|
||||
(advance! 1)
|
||||
(scan!)))
|
||||
((= ch ",")
|
||||
(do
|
||||
(dl-emit! "punct" "," start)
|
||||
(advance! 1)
|
||||
(scan!)))
|
||||
((= ch ".")
|
||||
(do
|
||||
(dl-emit! "punct" "." start)
|
||||
(advance! 1)
|
||||
(scan!)))
|
||||
((= ch "<")
|
||||
(do
|
||||
(dl-emit! "op" "<" start)
|
||||
(advance! 1)
|
||||
(scan!)))
|
||||
((= ch ">")
|
||||
(do
|
||||
(dl-emit! "op" ">" start)
|
||||
(advance! 1)
|
||||
(scan!)))
|
||||
((= ch "=")
|
||||
(do
|
||||
(dl-emit! "op" "=" start)
|
||||
(advance! 1)
|
||||
(scan!)))
|
||||
((= ch "+")
|
||||
(do
|
||||
(dl-emit! "op" "+" start)
|
||||
(advance! 1)
|
||||
(scan!)))
|
||||
((= ch "-")
|
||||
(do
|
||||
(dl-emit! "op" "-" start)
|
||||
(advance! 1)
|
||||
(scan!)))
|
||||
((= ch "*")
|
||||
(do
|
||||
(dl-emit! "op" "*" start)
|
||||
(advance! 1)
|
||||
(scan!)))
|
||||
((= ch "/")
|
||||
(do
|
||||
(dl-emit! "op" "/" start)
|
||||
(advance! 1)
|
||||
(scan!)))
|
||||
(else (error
|
||||
(str "Tokenizer: unexpected character '" ch
|
||||
"' at position " start)))))))))
|
||||
(scan!)
|
||||
(dl-emit! "eof" nil pos)
|
||||
tokens)))
|
||||
171
lib/datalog/unify.sx
Normal file
171
lib/datalog/unify.sx
Normal file
@@ -0,0 +1,171 @@
|
||||
;; lib/datalog/unify.sx — unification + substitution for Datalog terms.
|
||||
;;
|
||||
;; Term taxonomy (after parsing):
|
||||
;; variable — SX symbol whose first char is uppercase A–Z or '_'.
|
||||
;; constant — SX symbol whose first char is lowercase a–z (atom name).
|
||||
;; number — numeric literal.
|
||||
;; string — string literal.
|
||||
;; compound — SX list (functor arg ... arg). In core Datalog these
|
||||
;; only appear as arithmetic expressions (see Phase 4
|
||||
;; safety analysis); compound-against-compound unification
|
||||
;; is supported anyway for completeness.
|
||||
;;
|
||||
;; Substitutions are immutable dicts keyed by variable name (string).
|
||||
;; A failed unification returns nil; success returns the extended subst.
|
||||
|
||||
(define dl-empty-subst (fn () {}))
|
||||
|
||||
(define
|
||||
dl-var?
|
||||
(fn
|
||||
(term)
|
||||
(and
|
||||
(symbol? term)
|
||||
(let
|
||||
((name (symbol->string term)))
|
||||
(and
|
||||
(> (len name) 0)
|
||||
(let
|
||||
((c (slice name 0 1)))
|
||||
(or (and (>= c "A") (<= c "Z")) (= c "_"))))))))
|
||||
|
||||
;; Walk: chase variable bindings until we hit a non-variable or an unbound
|
||||
;; variable. The result is either a non-variable term or an unbound var.
|
||||
(define
|
||||
dl-walk
|
||||
(fn (term subst) (dl-walk-aux term subst (list))))
|
||||
|
||||
;; Internal: walk with a visited-var set so circular substitutions
|
||||
;; (from raw dl-bind misuse) don't infinite-loop. Cycles return the
|
||||
;; current term unchanged.
|
||||
(define
|
||||
dl-walk-aux
|
||||
(fn
|
||||
(term subst visited)
|
||||
(if
|
||||
(dl-var? term)
|
||||
(let
|
||||
((name (symbol->string term)))
|
||||
(cond
|
||||
((dl-member? name visited) term)
|
||||
((and (dict? subst) (has-key? subst name))
|
||||
(let ((seen (list)))
|
||||
(do
|
||||
(for-each (fn (v) (append! seen v)) visited)
|
||||
(append! seen name)
|
||||
(dl-walk-aux (get subst name) subst seen))))
|
||||
(else term)))
|
||||
term)))
|
||||
|
||||
;; Bind a variable symbol to a value in subst, returning a new subst.
|
||||
(define
|
||||
dl-bind
|
||||
(fn (var-sym value subst) (assoc subst (symbol->string var-sym) value)))
|
||||
|
||||
(define
|
||||
dl-unify
|
||||
(fn
|
||||
(t1 t2 subst)
|
||||
(if
|
||||
(nil? subst)
|
||||
nil
|
||||
(let
|
||||
((u1 (dl-walk t1 subst)) (u2 (dl-walk t2 subst)))
|
||||
(cond
|
||||
((dl-var? u1)
|
||||
(cond
|
||||
((and (dl-var? u2) (= (symbol->string u1) (symbol->string u2)))
|
||||
subst)
|
||||
(else (dl-bind u1 u2 subst))))
|
||||
((dl-var? u2) (dl-bind u2 u1 subst))
|
||||
((and (list? u1) (list? u2))
|
||||
(if
|
||||
(= (len u1) (len u2))
|
||||
(dl-unify-list u1 u2 subst 0)
|
||||
nil))
|
||||
((and (number? u1) (number? u2)) (if (= u1 u2) subst nil))
|
||||
((and (string? u1) (string? u2)) (if (= u1 u2) subst nil))
|
||||
((and (symbol? u1) (symbol? u2))
|
||||
(if (= (symbol->string u1) (symbol->string u2)) subst nil))
|
||||
(else nil))))))
|
||||
|
||||
(define
|
||||
dl-unify-list
|
||||
(fn
|
||||
(a b subst i)
|
||||
(cond
|
||||
((nil? subst) nil)
|
||||
((>= i (len a)) subst)
|
||||
(else
|
||||
(dl-unify-list
|
||||
a
|
||||
b
|
||||
(dl-unify (nth a i) (nth b i) subst)
|
||||
(+ i 1))))))
|
||||
|
||||
;; Apply substitution: walk the term and recurse into lists.
|
||||
(define
|
||||
dl-apply-subst
|
||||
(fn
|
||||
(term subst)
|
||||
(let
|
||||
((w (dl-walk term subst)))
|
||||
(if (list? w) (map (fn (x) (dl-apply-subst x subst)) w) w))))
|
||||
|
||||
;; Ground? — true iff no free variables remain after walking.
|
||||
(define
|
||||
dl-ground?
|
||||
(fn
|
||||
(term subst)
|
||||
(let
|
||||
((w (dl-walk term subst)))
|
||||
(cond
|
||||
((dl-var? w) false)
|
||||
((list? w) (dl-ground-list? w subst 0))
|
||||
(else true)))))
|
||||
|
||||
(define
|
||||
dl-ground-list?
|
||||
(fn
|
||||
(xs subst i)
|
||||
(cond
|
||||
((>= i (len xs)) true)
|
||||
((not (dl-ground? (nth xs i) subst)) false)
|
||||
(else (dl-ground-list? xs subst (+ i 1))))))
|
||||
|
||||
;; Return the list of variable names appearing in a term (deduped, in
|
||||
;; left-to-right order). Useful for safety analysis later.
|
||||
(define
|
||||
dl-vars-of
|
||||
(fn (term) (let ((seen (list))) (do (dl-vars-of-aux term seen) seen))))
|
||||
|
||||
(define
|
||||
dl-vars-of-aux
|
||||
(fn
|
||||
(term acc)
|
||||
(cond
|
||||
((dl-var? term)
|
||||
(let
|
||||
((name (symbol->string term)))
|
||||
(when (not (dl-member? name acc)) (append! acc name))))
|
||||
((list? term) (dl-vars-of-list term acc 0))
|
||||
(else nil))))
|
||||
|
||||
(define
|
||||
dl-vars-of-list
|
||||
(fn
|
||||
(xs acc i)
|
||||
(when
|
||||
(< i (len xs))
|
||||
(do
|
||||
(dl-vars-of-aux (nth xs i) acc)
|
||||
(dl-vars-of-list xs acc (+ i 1))))))
|
||||
|
||||
(define
|
||||
dl-member?
|
||||
(fn
|
||||
(x xs)
|
||||
(cond
|
||||
((= (len xs) 0) false)
|
||||
((= (first xs) x) true)
|
||||
(else (dl-member? x (rest xs))))))
|
||||
Reference in New Issue
Block a user