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#![allow(dead_code, unused_variables)]
//@ run-rustfix
// Check projection of an associated type out of a higher-ranked trait-bound
// in the context of a function signature.
pub trait Foo<T> {
type A;
fn get(&self, t: T) -> Self::A;
}
fn foo2<I : for<'x> Foo<&'x isize>>(
x: <I as Foo<&isize>>::A)
//~^ ERROR cannot use the associated type of a trait with uninferred generic parameters
{
// This case is illegal because we have to instantiate `'x`, and
// we don't know what region to instantiate it with.
//
// This could perhaps be made equivalent to the examples below,
// specifically for fn signatures.
}
fn foo3<I : for<'x> Foo<&'x isize>>(
x: <I as Foo<&isize>>::A)
{
// OK, in this case we spelled out the precise regions involved, though we left one of
// them anonymous.
}
fn foo4<'a, I : for<'x> Foo<&'x isize>>(
x: <I as Foo<&'a isize>>::A)
{
// OK, in this case we spelled out the precise regions involved.
}
pub fn main() {}
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