31 lines
542 B
Rust
31 lines
542 B
Rust
#![feature(const_trait_impl, effects, min_specialization, rustc_attrs)] //~ WARN the feature `effects` is incomplete
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#[rustc_specialization_trait]
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#[const_trait]
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pub trait Sup {}
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impl const Sup for () {}
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#[const_trait]
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pub trait A {
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fn a() -> u32;
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}
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#[const_trait]
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pub trait Spec {}
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impl<T: ~const Spec> const A for T {
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default fn a() -> u32 {
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2
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}
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}
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impl<T: Spec + Sup> A for T {
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//~^ ERROR: cannot specialize
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//FIXME(effects) ~| ERROR: missing `~const` qualifier
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fn a() -> u32 {
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3
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}
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}
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fn main() {}
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