34 lines
557 B
Rust
34 lines
557 B
Rust
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// check-pass
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use std::marker::PhantomData;
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trait Lt<'a> {
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type T;
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}
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struct Id<T>(PhantomData<T>);
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impl<'a,T> Lt<'a> for Id<T> {
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type T = T;
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}
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struct Ref<T>(PhantomData<T>) where T: ?Sized;
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impl<'a,T> Lt<'a> for Ref<T>
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where T: 'a + Lt<'a> + ?Sized
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{
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type T = &'a T;
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}
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struct Mut<T>(PhantomData<T>) where T: ?Sized;
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impl<'a,T> Lt<'a> for Mut<T>
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where T: 'a + Lt<'a> + ?Sized
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{
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type T = &'a mut T;
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}
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struct C<I,O>(for<'a> fn(<I as Lt<'a>>::T) -> O) where I: for<'a> Lt<'a>;
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fn main() {
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let c = C::<Id<_>,_>(|()| 3);
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c.0(());
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}
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