33 lines
719 B
Rust
33 lines
719 B
Rust
#![feature(generic_const_exprs)]
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#![allow(incomplete_features)]
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trait _Contains<T> {
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const does_contain: bool;
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}
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trait Contains<T, const Satisfied: bool> {}
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trait Delegates<T> {}
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impl<T, U> Delegates<U> for T where T: Contains<U, true> {}
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const fn contains<A, B>() -> bool
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where
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A: _Contains<B>,
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{
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A::does_contain
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}
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impl<T, U> Contains<T, { contains::<T, U>() }> for U where T: _Contains<U> {}
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fn writes_to_path<C>(cap: &C) {
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writes_to_specific_path(&cap);
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//~^ ERROR: the trait bound `(): _Contains<&C>` is not satisfied [E0277]
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//~| ERROR: unconstrained generic constant
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//~| ERROR: mismatched types [E0308]
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}
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fn writes_to_specific_path<C: Delegates<()>>(cap: &C) {}
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fn main() {}
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