30 lines
629 B
Rust
30 lines
629 B
Rust
// Tests that specializing trait impls must be at least as const as the default impl.
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//@ revisions: spec min_spec
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#![feature(const_trait_impl)]
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#![cfg_attr(spec, feature(specialization))]
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//[spec]~^ WARN the feature `specialization` is incomplete
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#![cfg_attr(min_spec, feature(min_specialization))]
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#[const_trait]
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trait Value {
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fn value() -> u32;
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}
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impl<T> const Value for T {
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default fn value() -> u32 {
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0
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}
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}
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struct FortyTwo;
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impl Value for FortyTwo {
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//~^ ERROR conflicting implementations
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fn value() -> u32 {
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println!("You can't do that (constly)");
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42
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}
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}
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fn main() {}
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