mirror of https://github.com/rust-lang/rust
30 lines
408 B
Rust
30 lines
408 B
Rust
//@ build-pass
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trait AssociatedConstant {
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const DATA: ();
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}
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impl<F, T> AssociatedConstant for F
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where
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F: FnOnce() -> T,
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T: AssociatedConstant,
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{
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const DATA: () = T::DATA;
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}
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impl AssociatedConstant for () {
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const DATA: () = ();
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}
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fn foo() -> impl AssociatedConstant {
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()
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}
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fn get_data<T: AssociatedConstant>(_: T) -> &'static () {
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&T::DATA
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}
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fn main() {
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get_data(foo);
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}
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