35 lines
620 B
Rust
35 lines
620 B
Rust
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// Test that we are able to establish that `<T as
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// MyTrait<'a>>::Output` outlives `'b` here. We need to prove however
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// that `<T as MyTrait<'a>>::Output` outlives `'a`, so we also have to
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// prove that `'b: 'a`.
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trait MyTrait<'a> {
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type Output;
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}
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fn foo1<'a, 'b, T>() -> &'a ()
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where
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T: MyTrait<'a>,
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<T as MyTrait<'a>>::Output: 'b,
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{
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bar::<T::Output>() //~ ERROR may not live long enough
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}
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fn foo2<'a, 'b, T>() -> &'a ()
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where
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T: MyTrait<'a>,
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<T as MyTrait<'a>>::Output: 'b,
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'b: 'a,
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{
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bar::<T::Output>() // OK
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}
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fn bar<'a, T>() -> &'a ()
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where
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T: 'a,
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{
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&()
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}
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fn main() {}
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