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