matche-pattern->expr now treats keyword patterns as literals that emit
themselves bare, rather than wrapping in (quote ...). SX keywords
self-evaluate to their string name; quoting them flips them to a
keyword type that does not unify with the bare-keyword usage at the
target site. This was visible only as a test failure on the diffo
clauses below — tightened the pattern rules.
tests/classics.sx exercises three end-to-end miniKanren programs:
- 3-friend / 3-pet permutation puzzle
- grandparent inference over a fact list (membero + fresh)
- symbolic differentiation dispatched by matche on
:x / (:+ a b) / (:* a b)
228/228 cumulative.
Pattern grammar: _, symbol, atom (number/string/keyword/bool), (), and
(p1 ... pn) list patterns (recursive). Symbols become fresh vars in a
fresh form, atoms become literals to unify against, lists recurse
position-wise. Repeated names produce the same fresh var (so they
unify by ==).
Macro is built with explicit cons/list rather than a quasiquote because
the quasiquote expander does not recurse into nested lambda bodies —
the natural `\`(matche-clause (quote ,target) cl)` spelling left
literal `(unquote target)` forms in the output.
14 tests, 222/222 cumulative. Phase 5 done (project, conda, condu,
onceo, nafc, matche all green).
