#moonrockz/wac

WAC language tooling for MoonBit.

Source positions, structured diagnostics, a lossless scanner, typed immutable ASTs/CSTs and a recovering parser, immutable traversal, rewrites, canonical printing and comment-preserving formatting are implemented. Install with moon add moonrockz/wac@0.1.0.

#Scope

Package/targets directives, WIT-style definitions supported by the WAC reference, imports, let bindings, instantiations, access expressions, spread arguments and exports.

Syntax parsing is separate from semantic resolution. Cross-file/package loading, name resolution, registry access and composition evaluation belong in later semantic tooling. The syntax parser must not perform I/O.

#Packages

Package	Responsibility
span	Source text, positions and documented Unicode offset units
diagnostic	Stable codes, severity, source labels and recovery details
scanner	Lossless tokens, comments and whitespace
ast	Immutable typed nodes and child collections
cst	Immutable lossless concrete structure, including malformed input
parser	Recovering source-to-AST/CST parsing with diagnostics
traversal	Explicit-stack walks, folds, reductions, events, cursors and immutable rewrites
printer	Stack-safe canonical AST-to-source emission
formatter	Stack-safe CST formatting that preserves comments and meaning

#Validation

Upstream valid and invalid fixtures pinned to the reference linked in the root README.
Exact scanner/CST reconstruction, including Unicode, comments and malformed text.
Diagnostic recovery, progress through arbitrary input and no-panic properties.
Deep types, groups and instantiations on every target.

Traversal tests cover canonical event order, prune/stop, cursors, immutable rewrites and all 46 node kinds. Printer round trips and formatter idempotence/token-preservation laws cover all corpus files and deep WAC composition expressions. The parser profile documents the pinned corpus and WIT grammar differences.

See root Beads epic wasm-devkit-p5m for implementation work.