3 Commits

Author	SHA1	Message	Date
giles	23a53a2ccb	scheme: Phase 3 — if/define/set!/begin/lambda/closures + 24 tests ... eval.sx grows: five new syntactic operators wired via the table- driven dispatch from Phase 2. lambda creates closures {:scm-tag :closure :params :rest :body :env} that capture the static env; scheme-apply-closure binds formals + rest-arg, evaluates multi-expression body in (extend static-env), returns last value. Supports lambda formals shapes: () → no args (a b c) → fixed arity args → bare symbol; binds all call-args as a list Dotted-pair tail (a b . rest) deferred until parser supports it. define has both flavours: (define name expr) — direct binding (define (name . formals) body...) — lambda sugar set! walks the env chain via refl-env-find-frame, mutates at the binding's source frame (no shadowing). Raises on unbound name. 24 new tests in lib/scheme/tests/syntax.sx, including: - Factorial 5 → 120 and 10 → 3628800 (recursion + closures) - make-counter via closed-over set! state - Curried (((curry+ 1) 2) 3) → 6 - (lambda args args) rest-arg binding - Multi-body lambdas with internal define 109 total Scheme tests (62 parse + 23 eval + 24 syntax).	2026-05-13 20:02:46 +00:00
giles	e222e8b0aa	scheme: Phase 2 evaluator — env.sx third consumer + 23 tests [consumes-env] ... lib/scheme/eval.sx — R7RS evaluator skeleton: - Self-evaluating: numbers, booleans, characters, vectors, strings - Symbol lookup: refl-env-lookup - Lists: syntactic-operator table dispatch, else applicative call - Table-driven syntactic ops (Phase 2 wires `quote` only; full set in Phase 3) - Apply: callable host fn or scheme closure (closure stub for Phase 3) scheme-make-env / scheme-env-bind! / etc. are THIN ALIASES for the refl-env-* primitives from lib/guest/reflective/env.sx. No adapter cfg needed — Scheme's lexical-scope semantics ARE the canonical wire shape. This is the THIRD CONSUMER for env.sx after Kernel and Tcl + Smalltalk's variant adapters; the first to use it without any bridging code. Validates the kit handles canonical-shape adoption with zero ceremony. 23 tests in lib/scheme/tests/eval.sx cover literals, symbol lookup with parent-chain shadowing, quote (special form + sugar), primitive application with nested calls, and an env-as-value section explicitly demonstrating the kit primitives work on Scheme envs. 85 total Scheme tests (62 parse + 23 eval). chisel: consumes-env (third consumer for lib/guest/reflective/env.sx).	2026-05-13 20:00:36 +00:00
giles	c919d9a0d7	scheme: Phase 1 parser — R7RS lexical reader + 62 tests [consumes-lex] ... lib/scheme/parser.sx — reader for R7RS-small lexical syntax: - numbers (int/float/exp) - booleans #t / #f / #true / #false - strings with standard escapes - symbols (permissive — any non-delimiter) - characters #\c, #\space, #\newline, #\tab, etc. - vectors #(...) - proper lists (dotted-pair deferred to Phase 3 with lambda rest-args) - reader macros: 'X `X ,X ,@X → (quote X) (quasiquote X) etc. (Scheme conventions — lowercase, no $ prefix) - line comments ; - nestable block comments #| ... |# - datum comments #;<datum> AST shape mirrors Kernel: numbers/booleans/lists pass through; strings wrapped as {:scm-string ...} to distinguish from symbols (bare SX strings); chars as {:scm-char ...}; vectors as {:scm-vector (list ...)}. 62 tests in lib/scheme/tests/parse.sx cover atom kinds, escape sequences, quote/quasiquote/unquote/unquote-splicing, all three comment flavours, and classic Scheme idioms (lambda, define, let, if-cond). Note: SX cond branches evaluate only the LAST expression, so multi-mutation branches need explicit (do ...) or (begin ...) wrappers — caught during block-comment debugging. chisel: consumes-lex (lex-digit?, lex-whitespace? from lib/guest/lex.sx); pratt not consumed (no operator precedence in Scheme).	2026-05-13 19:58:30 +00:00