34 lines
475 B
Rust
34 lines
475 B
Rust
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// check-pass
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fn any<T>() -> T {
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loop {}
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}
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trait Foo {
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type V;
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}
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trait Callback<T: Foo>: Fn(&T, &T::V) {}
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impl<T: Foo, F: Fn(&T, &T::V)> Callback<T> for F {}
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struct Bar<T: Foo> {
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callback: Box<dyn Callback<T>>,
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}
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impl<T: Foo> Bar<T> {
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fn event(&self) {
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(self.callback)(any(), any());
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}
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}
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struct A;
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struct B;
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impl Foo for A {
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type V = B;
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}
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fn main() {
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let foo = Bar::<A> { callback: Box::new(|_: &A, _: &B| ()) };
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foo.event();
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}
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