Orkuncakilkaya
0d1b09e4f0
A fallible function returns a `result` value, built with ok(payload) on success
or err(message) on failure. The caller recovers a value with `try EXPR else {
… }`: on ok the whole expression is the payload; on err the else block runs —
with the failure message bound to `error` — and its trailing expression supplies
the fallback. It is a plain branch on the result's tag: no exceptions, no hidden
control flow, nothing unwinds. is_ok(r) / is_err(r) classify without unwrapping.
Payloads are any i32-width scalar (int/fixed/bool/entity). The feature is
additive and only kicks in when ok/err/try are used, so untouched programs
compile byte-identically (verified) and the C-free bootstrap fixpoint holds.
Complements panic/assert from #8 (the unrecoverable half). The optional
top-level frame `recover` stays deferred (needs a frame-abort mechanism); the
full tagged-union/any generalization is tracked in #1.
Adds the `try` keyword and ok/err/is_ok/is_err builtins across the compiler,
the vocabulary header, JetBrains + TextMate/VSCode grammars, the docs inventory
and pages, examples/library/recover.ludic, and a regression case.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
1 KiB
bump: minor
type: feat
Recoverable failures as values (#46) — a fallible function returns a result (a new value type), built with ok(payload) on success or err(message) on failure, and the caller recovers a value with try EXPR else { … }: on ok the whole expression is the payload, on err the else block runs — with the failure message bound to error — and its trailing expression supplies the fallback. It is a plain branch on the result's tag: no exceptions, no hidden control flow, nothing unwinds the stack. is_ok(r) / is_err(r) classify a result without unwrapping it. Payloads are any i32-width scalar (int/fixed/bool/entity); the whole feature is additive and only kicks in when ok/err/try are used, so programs that don't touch it compile byte-identically. Complements panic/assert from #8, which handle the unrecoverable programmer-bug half. The optional top-level frame recover remains deferred (it needs a frame-abort/unwind mechanism); the full tagged-union/any generalization is tracked in #1.