Spec Update: Batch 08 — Specs (Traits)

Date: 2026-04-16 Plans Referenced: Plan 019 (specs), Plan 057 (generic specs), Plan 059 (spec impl) Source Files: ast/spec.rs (SpecDecl, SpecImpl, SpecMethod) Sections Updated: Specs (Traits) (Section 13 — NEW)

Old Content

No dedicated spec/trait section existed. The has keyword was listed but not documented.

New Content

Spec Declaration

• spec Printable { fn print() void }
• Generic specs: spec Iterable<T> { ... }
• Default methods: fn log(msg str) void { ... }

Spec Implementation

• type User has Printable { ... }
• Multiple spec impls: type File has Readable, Writable { ... }

SpecDecl Fields

• name, generic_params, methods, is_pub

Transpilation Behavior

• C: vtables (struct of function pointers)
• Rust: native traits
• VM: dynamic dispatch via method registry

Notes

• has keyword used for spec implementation declaration on types
• Spec methods with body provide default implementations (Plan 019 Stage 8.5)
• SpecImpl struct tracks spec_name and type_args for generic spec instances