mirror of https://github.com/rust-lang/rust
36 lines
804 B
Rust
36 lines
804 B
Rust
// Test that `impl MyTrait<'_> for &i32` is equivalent to `impl<'a,
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// 'b> MyTrait<'a> for &'b i32`.
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//
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//@ run-pass
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#![allow(warnings)]
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trait MyTrait<'a> { }
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// This is equivalent to `MyTrait<'a> for &'b i32`, which is proven by
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// the code below.
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impl MyTrait<'_> for &i32 {
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}
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// When called, T will be `&'x i32` for some `'x`, so since we can
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// prove that `&'x i32: for<'a> MyTrait<'a>, then we know that the
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// lifetime parameter above is disconnected.
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fn impls_my_trait<T: for<'a> MyTrait<'a>>() { }
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fn impls_my_trait_val<T: for<'a> MyTrait<'a>>(_: T) {
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impls_my_trait::<T>();
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}
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fn random_where_clause()
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where for<'a, 'b> &'a i32: MyTrait<'b> { }
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fn main() {
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let x = 22;
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let f = &x;
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impls_my_trait_val(f);
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impls_my_trait::<&'static i32>();
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random_where_clause();
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}
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