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// Illustrates the "projection gap": in this test, even though we know
// that `T::Foo: 'x`, that does not tell us that `T: 'x`, because
// there might be other ways for the caller of `func` to show that
// `T::Foo: 'x` holds (e.g., where-clause).
trait Trait1<'x> {
type Foo;
}
// calling this fn should trigger a check that the type argument
// supplied is well-formed.
fn wf<T>() { }
fn func<'x, T:Trait1<'x>>(t: &'x T::Foo)
{
wf::<&'x T>();
//~^ ERROR the parameter type `T` may not live long enough
}
fn caller2<'x, T:Trait1<'x>>(t: &'x T)
{
wf::<&'x T::Foo>(); // OK
}
fn caller3<'x, T:Trait1<'x>>(t: &'x T::Foo)
{
wf::<&'x T::Foo>(); // OK
}
fn main() { }
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