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>
890 B
890 B
id: fn-is_ok name: is_ok category: builtins kind: builtin tokens: is_ok sig: is_ok(r: result) -> bool tip: True when a result carries a success payload. order: 14
Tests a result's tag: true when it was built with ok, false when it was built with err. Use it when you want to branch on success without unwrapping the payload — the payload itself is recovered with try/else. It is the exact negation of is_err.
Parameters:
r— the result to test
program Check {
function find(x: int) -> result {
if x == 7 { return ok(x) }
return err("missing")
}
test "is_ok classifies without unwrapping" {
expect(is_ok(find(7)))
expect(not is_ok(find(3)))
}
}