56 lines
908 B
Rust
56 lines
908 B
Rust
// check-pass
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#![feature(const_trait_impl, min_specialization, rustc_attrs)]
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#[rustc_specialization_trait]
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#[const_trait]
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pub unsafe trait Sup {
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fn foo() -> u32;
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}
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#[rustc_specialization_trait]
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#[const_trait]
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pub unsafe trait Sub: ~const Sup {}
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unsafe impl const Sup for u8 {
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default fn foo() -> u32 {
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1
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}
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}
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unsafe impl const Sup for () {
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fn foo() -> u32 {
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42
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}
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}
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unsafe impl const Sub 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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impl<T: ~const Default> 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: ~const Default + ~const Sup> const A for T {
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default fn a() -> u32 {
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3
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}
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}
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impl<T: ~const Default + ~const Sub> const A for T {
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fn a() -> u32 {
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T::foo()
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}
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}
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const _: () = assert!(<()>::a() == 42);
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const _: () = assert!(<u8>::a() == 3);
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const _: () = assert!(<u16>::a() == 2);
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fn main() {}
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