bootstrap_js.py reads the reference .sx specification (eval.sx, render.sx)
and transpiles the defined evaluator functions into standalone JavaScript.
The output sx-ref.js is a fully functional SX evaluator bootstrapped from
the s-expression spec, comparable against the hand-written sx.js.
Key features:
- JSEmitter class transpiles SX AST → JS (fn→function, let→IIFE, cond→ternary, etc.)
- Platform interface (types, env ops, primitives) implemented as native JS
- Post-transpilation fixup wraps callLambda to handle both Lambda objects and primitives
- 93/93 tests passing: arithmetic, strings, control flow, closures, HO forms,
components, macros, threading, dict ops, predicates
Fixed during development:
- Bool before int isinstance check (Python bool is subclass of int)
- SX NIL sentinel detection (not Python None)
- Cond style detection (determine Scheme vs Clojure once, not per-pair)
- Predicate null safety (x != null instead of x && to avoid 0-as-falsy in SX)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Meta-circular evaluator: the SX language specifying its own semantics.
A thin bootstrap compiler per target (JS, Python, Rust) reads these
.sx files and emits a native evaluator.
Files:
- eval.sx: Core evaluator — type dispatch, special forms, TCO trampoline,
lambda/component/macro invocation, higher-order forms
- primitives.sx: Declarative specification of ~80 built-in pure functions
- render.sx: Three rendering modes (DOM, HTML string, SX wire format)
- parser.sx: Tokenizer, parser, and serializer specification
Platform-specific concerns (DOM ops, async I/O, HTML emission) are
declared as interfaces that each target implements.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
