Orkuncakilkaya
790eda6f73
Types phase 3 — the option/result safety pair. result/ok/err/try shipped in #46; this adds its companion option: - some(v) -> option (present value; any i32-width scalar) - none() -> option (empty; no magic -1 sentinel) - is_some / is_none -> bool - unwrap_or(o, fallback) -> int A heap %Option = { i32 present, i32 value }, bare builtins guarded by find_fn (a user fn of the same name still wins), gated by g_uses_option so unused programs compile byte-identically — same idiom as result. Wired: emit_call codegen + %Option decl (emit_decl) + g_uses_option (emit_core), reseeded seed, vocabulary sync (header/JetBrains/TextMate), builtin docs + inventory, and a self-asserting example (examples/library/optionresult.ludic + feat_case). All suites green incl. golden renders byte-identical and the bootstrap fixpoint. Tagged-union enums (variant payloads + binding match + exhaustiveness) are the deep type-system feature, split out to #56. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
24 lines
763 B
Markdown
24 lines
763 B
Markdown
---
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id: fn-none
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name: none
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category: builtins
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kind: builtin
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tokens: none
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sig: none() -> option
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tip: The empty option — a missing value.
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order: 17
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---
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The empty <code>option</code> — a missing value with no sentinel. Return it when there is nothing to give: no target, an empty slot, a lookup that missed. The caller distinguishes it from <a href="fn-some"><code>some</code></a> with <a href="fn-is_none"><code>is_none</code></a> / <a href="fn-is_some"><code>is_some</code></a>, or supplies a default with <a href="fn-unwrap_or"><code>unwrap_or</code></a>.
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```ludic
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program Slots {
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function held(slot: int) -> option {
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if slot < 0 { return none() }
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return some(slot)
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}
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test "none is empty" {
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expect_eq(is_none(held(0 - 1)), true)
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}
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}
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```
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