// 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() { } 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() { }