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21 lines
380 B
Rust
21 lines
380 B
Rust
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pub trait MakeRef<'a> {
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type Ref;
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}
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impl<'a, T: 'a> MakeRef<'a> for T {
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type Ref = &'a T;
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}
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pub trait MakeRef2 {
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type Ref2;
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}
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impl<'a, T: 'a> MakeRef2 for T {
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//~^ ERROR the lifetime parameter `'a` is not constrained
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type Ref2 = <T as MakeRef<'a>>::Ref;
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}
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fn foo() -> <String as MakeRef2>::Ref2 { &String::from("foo") }
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fn main() {
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println!("{}", foo());
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}
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