29 lines
592 B
Rust
29 lines
592 B
Rust
//@ run-pass
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// Tests for RFC 1268: we allow overlapping impls of marker traits,
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// that is, traits without items. In this case, a type `T` is
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// `MyMarker` if it is either `Debug` or `Display`.
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#![feature(marker_trait_attr)]
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#![feature(negative_impls)]
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use std::fmt::{Debug, Display};
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#[marker]
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trait MyMarker {}
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impl<T: Debug> MyMarker for T {}
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impl<T: Display> MyMarker for T {}
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fn foo<T: MyMarker>(t: T) -> T {
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t
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}
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fn main() {
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// Debug && Display:
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assert_eq!(1, foo(1));
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assert_eq!(2.0, foo(2.0));
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// Debug && !Display:
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assert_eq!(vec![1], foo(vec![1]));
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}
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