mirror of https://github.com/rust-lang/rust
43 lines
725 B
Rust
43 lines
725 B
Rust
// Test equality constraints on associated types. Check we get type errors
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// where we should.
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pub trait Foo {
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type A;
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fn boo(&self) -> <Self as Foo>::A;
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}
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struct Bar;
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impl Foo for isize {
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type A = usize;
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fn boo(&self) -> usize {
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42
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}
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}
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fn foo1<I: Foo<A=Bar>>(x: I) {
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let _: Bar = x.boo();
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}
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fn foo2<I: Foo>(x: I) {
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let _: Bar = x.boo();
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//~^ ERROR mismatched types
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//~| found associated type `<I as Foo>::A`
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//~| expected `Bar`, found
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//~| expected struct `Bar`
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}
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pub fn baz(x: &dyn Foo<A=Bar>) {
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let _: Bar = x.boo();
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}
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pub fn main() {
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let a = 42;
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foo1(a);
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//~^ ERROR type mismatch resolving
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baz(&a);
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//~^ ERROR type mismatch resolving
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}
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