33 lines
450 B
Rust
33 lines
450 B
Rust
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//@ check-pass
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#![feature(never_type, exhaustive_patterns)]
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trait Tag {
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type TagType;
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}
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enum Keep {}
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enum Erase {}
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impl Tag for Keep {
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type TagType = ();
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}
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impl Tag for Erase {
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type TagType = !;
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}
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enum TagInt<T: Tag> {
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Untagged(i32),
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Tagged(T::TagType, i32)
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}
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fn test(keep: TagInt<Keep>, erase: TagInt<Erase>) {
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match erase {
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TagInt::Untagged(_) => (),
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TagInt::Tagged(_, _) => ()
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};
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}
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fn main() {}
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