Tya v0.47 Release Notes

Status: shipped. The tya version constant is 0.47.0 and ROADMAP.md carries the matching Released entry.

TL;DR

v0.47 is the clean-cut release that retires the legacy v0.45 class-member surface (@, @@, _-prefix, init / _init) that v0.46 kept alive for backward compatibility. The v0.46 keyword surface (private, static, self, Self, initialize) is now the only way to write a class outside the selfhost/v01/ self-host tree.

Diagnostics wired

Code	Stage	Condition
`[TYA-E0407]`	checker	Class member name begins with `_`.
`[TYA-E0410]`	checker	`@field` or `@@field` sigil used.
`[TYA-E0411]`	checker	`self` used inside a `static` method.
`[TYA-E0412]`	checker	`Self` used outside a class body.
`[TYA-E0414]`	checker	Class declares `init` / `_init`; expected `initialize`.

Migration

The same mechanical rewrites listed in v0.46’s release notes apply. After v0.47, user code MUST use the new surface; the legacy syntax raises diagnostics. Affected forms:

@name             →  self.name
@name = x         →  self.name = x
@@count           →  Self.count
@@count = 0       →  static count = 0
@@count = x       →  Self.count = x
_name = ...       →  private name = ...
_init = name -> …  →  private initialize = name -> …
init = name -> …  →  initialize = name -> …

All of examples/, stdlib/, and tests/testdata/v*/ were migrated to the new surface in this release. The single fixture that pinned legacy-only error messages (v09/private_members) was retired — the underlying _-prefix privacy heuristic is gone.

Self-Host Constraint

selfhost/v01/compiler.tya uses the v0.43 surface (@, @@, _-prefix, init). The Go reference implementation enters permissive legacy mode on the checker when the entry path is under selfhost/v01/. This skips the E0407 / E0410 / E0411 / E0414 diagnostics for that sub-tree. User code is not in that path and is subject to the new rules.

The mechanism is checker.SetPermissiveLegacy(bool), called by the runner and cmd/tya entry points after deriving the legacy flag from the input file path via runner.IsLegacyV01Path(path).

TestSelfhostV01Scripts continues to pass; the v01 compiler self-compiles unchanged.

Deferred to future minors

G1 (strict bare-name receivers) — full elimination of bare-name → class-member fallback in the checker’s identifier resolution. Today bare names resolve through scope; the v0.47 diagnostics catch the most common legacy paths, but a complete G1 enforcement requires walking the resolver and proving no field/static fallback can fire. Tracked for v0.48.
G6 (formatter rewrite) — <DeclaringClass>.foo → Self.foo inside the declaring class body, plus [TYA-E0413] strict-mode warning. Tracked for v0.48.

Verification

go test ./... -count=1
go test ./tests -run TestSelfhostV01Scripts -count=1

All green at the v0.47.0 tag. The v0.46 TestV46Scripts and v0.45 TestV45Scripts continue to pass on the migrated fixtures.

Cross-References

docs/v0.47/SPEC.md — frozen v0.47 specification.
docs/v0.46/SPEC.md — the surface v0.47 finalizes.
docs/v0.46/RELEASE_NOTES.md — the transitional release listing what v0.47 retires.
ROADMAP.md — Released § v0.47.