Tya v0.39 Specification — Canonical Syntax (Surface Cleanup)

Tya v0.39 finalizes the Canonical Syntax surface that landed in v0.38. The formatter subcommand is now spelled with the full word tya format, and its style opt-outs are removed: there is exactly one canonical layout, with no flag to disable any of it.

This release is purely a CLI-surface tightening. The serializer, parser, and AST changes were already shipped in v0.38; v0.39 just removes the transitional spellings.

Goals (v0.39)

• The formatter subcommand is tya format. The legacy short spelling tya fmt is rejected with a structured hint.
• The transitional --text and --ast opt-outs are removed from tya format. The AST-driven canonical serializer is the only user-visible behavior; the text-pass fallback for unsupported inputs is now an invisible safety net rather than a flag.
• --text typed by a user yields unknown format option: --text.
• --ast typed by a user yields unknown format option: --ast.

Non-Goals (v0.39)

• Any change to the canonical layout produced by the formatter.
• Any change to the parser, AST, lexer, or runtime.
• Any change to comment-position diagnostics (still TYA-E0150, emitted by tya check).

CLI Surface

tya format [-w] [path]

There are no other flags. --text, --ast, and any other style flag are rejected.

tya fmt returns exit code 2 with a structured hint pointing at tya format.

Self-Host Invariant

No language change; the self-host fixed point holds. TestSelfhostV01Scripts continues to pass.

Acceptance Criteria

A v0.39 build is acceptable when:

1. tya format path.tya prints canonical output.
2. tya format -w path.tya writes canonical output in place.
3. tya format --text path.tya and tya format --ast path.tya both fail with unknown format option: ….
4. tya fmt path.tya fails with a hint pointing at tya format.
5. go test ./... -count=1 passes, including the self-host invariant.

References

• docs/CANONICAL_SYNTAX.md — the authoritative canonical-syntax specification.
• v0.38 SPEC: Canonical Syntax landing.