mirror of https://github.com/rust-lang/rust
39 lines
726 B
Rust
39 lines
726 B
Rust
//@ run-pass
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// Test references to the trait `Stream` in the bounds for associated
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// types defined on `Stream`. Issue #20551.
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trait Stream {
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type Car;
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type Cdr: Stream;
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fn car(&self) -> Self::Car;
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fn cdr(self) -> Self::Cdr;
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}
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impl Stream for () {
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type Car = ();
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type Cdr = ();
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fn car(&self) -> () { () }
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fn cdr(self) -> () { self }
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}
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impl<T,U> Stream for (T, U)
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where T : Clone, U : Stream
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{
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type Car = T;
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type Cdr = U;
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fn car(&self) -> T { self.0.clone() }
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fn cdr(self) -> U { self.1 }
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}
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fn main() {
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let p = (22, (44, (66, ())));
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assert_eq!(p.car(), 22);
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let p = p.cdr();
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assert_eq!(p.car(), 44);
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let p = p.cdr();
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assert_eq!(p.car(), 66);
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}
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