mirror of https://github.com/rust-lang/rust
28 lines
531 B
Rust
28 lines
531 B
Rust
//@ run-pass
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// nb: does not impl Default
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#[derive(Debug, PartialEq)]
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struct NotDefault;
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#[derive(Debug, Default, PartialEq)]
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enum Foo {
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#[default]
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Alpha,
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#[allow(dead_code)]
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Beta(NotDefault),
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}
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// #[default] on a generic enum does not add `Default` bounds to the type params.
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#[derive(Default)]
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enum MyOption<T> {
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#[default]
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None,
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#[allow(dead_code)]
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Some(T),
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}
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fn main() {
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assert_eq!(Foo::default(), Foo::Alpha);
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assert!(matches!(MyOption::<NotDefault>::default(), MyOption::None));
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}
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