Commit Graph

2 Commits

Author SHA1 Message Date
e222e8b0aa scheme: Phase 2 evaluator — env.sx third consumer + 23 tests [consumes-env]
Some checks failed
Test, Build, and Deploy / test-build-deploy (push) Failing after 25s
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
c919d9a0d7 scheme: Phase 1 parser — R7RS lexical reader + 62 tests [consumes-lex]
Some checks failed
Test, Build, and Deploy / test-build-deploy (push) Failing after 21s
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