21 lines
586 B
Rust
21 lines
586 B
Rust
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enum pattern { tabby, tortoiseshell, calico }
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enum breed { beagle, rottweiler, pug }
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type name = str;
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enum ear_kind { lop, upright }
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enum animal { cat(pattern), dog(breed), rabbit(name, ear_kind), tiger }
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fn noise(a: animal) -> option<str> {
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alt a {
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cat(*) { some("meow") }
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dog(*) { some("woof") }
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rabbit(*) { none }
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tiger(*) { some("roar") }
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}
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}
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fn main() {
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assert noise(cat(tabby)) == some("meow");
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assert noise(dog(pug)) == some("woof");
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assert noise(rabbit("Hilbert", upright)) == none;
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assert noise(tiger) == some("roar");
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}
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