20 lines
315 B
Rust
20 lines
315 B
Rust
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#![feature(const_trait_impl)]
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#[const_trait]
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trait Tr {
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fn a(self) -> i32;
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}
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impl Tr for () {
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fn a(self) -> i32 { 42 }
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}
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const fn need_const_closure<T: ~const FnOnce(()) -> i32>(x: T) -> i32 {
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x(())
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}
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const _: () = assert!(need_const_closure(Tr::a) == 42);
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//~^ ERROR: the trait bound
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fn main() {}
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