28 lines
360 B
Rust
28 lines
360 B
Rust
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// check-pass
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struct D;
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trait Tr {
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type It;
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fn foo(self) -> Option<Self::It>;
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}
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impl<'a> Tr for &'a D {
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type It = ();
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fn foo(self) -> Option<()> { None }
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}
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fn run<F>(f: F)
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where for<'a> &'a D: Tr,
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F: Fn(<&D as Tr>::It),
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{
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let d = &D;
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while let Some(i) = d.foo() {
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f(i);
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}
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}
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fn main() {
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run(|_| {});
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}
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