Tya v0.64 Release Notes

v0.64 adds first-class lexical closures, iterable sequence protocols, and a set of standard-library protocol interfaces for comparison, equality, I/O, serialization, and human-readable string conversion.

Language

• Lexical closures now capture free variables across compile-to-C boundaries, including nested function literals and captured values that must survive GC.
• The checker rejects unsupported captured-binding indexed/member mutation with a stable diagnostic while preserving legacy self-host compatibility where it is still required.

Iteration

• Iterator, Iterable, and Sequence define the standard iteration protocol used by for ... in.
• Arrays, dictionaries, and strings can be consumed through the protocol without boxing their primitive values.
• Sequence helpers provide lazy map, filter, take, and to_a composition over iterable values.

Standard Protocols

• Comparable defines compare(other) with derived lt?, lte?, gt?, gte?, and between? helpers. Primitive numbers and strings expose the same methods.
• Equatable defines equal?(other). Primitive scalar values follow normal runtime equality, while arrays and dictionaries use deep equality.
• io now exposes Readable, Writable, Closable, and Flushable protocol interfaces. Existing io.Reader, io.Writer, net/socket.Socket, and net/socket.Server declare the matching contracts.
• serialization.Serializable defines to_data() as the canonical structured serialization hook. Serializer.to_data prefers it over the older to_serialized() hook.
• Stringable defines the human-readable to_s() protocol and documents the primitive conformance rule for Number, String, Array, Dict, Boolean, and Nil.

Documentation

• docs/SPEC.md, docs/API.md, and docs/STDLIB.md document the new protocols and distinguish Stringable.to_s() from Serializable.to_data().
• Completed PRDs for the release were moved to feature-specs/completed/.

Verification

The release gate is:

go test ./... -count=1

On the release machine, the full suite exceeded Go’s default 10-minute package timeout after all tests were already in the long tya/tests package. The same release gate with an explicit 20-minute timeout passed:

go test ./... -count=1 -timeout=20m