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// In this fn, the type `F` is a function that takes a reference to a
// struct and returns another reference with the same lifetime.
//
// Meanwhile, the bare fn `foo` takes a reference to a struct with
// *ANY* lifetime and returns a reference with the 'static lifetime.
// This can safely be considered to be an instance of `F` because all
// lifetimes are sublifetimes of 'static.
#![allow(dead_code)]
#![allow(unused_variables)]
struct S;
// Given 'cx, return 'cx
type F = for<'cx> fn(&'cx S) -> &'cx S;
fn want_F(f: F) {}
// Given anything, return 'static
type G = for<'cx> fn(&'cx S) -> &'static S;
fn want_G(f: G) {}
// Should meet both.
fn foo(x: &S) -> &'static S {
panic!()
}
// Should meet both.
fn bar<'a, 'b>(x: &'a S) -> &'b S {
panic!()
}
// Meets F, but not G.
fn baz(x: &S) -> &S {
panic!()
}
fn supply_F() {
want_F(foo);
want_F(bar);
want_F(baz);
}
fn supply_G() {
want_G(foo);
want_G(bar);
want_G(baz); //~ ERROR mismatched types
}
pub fn main() {}
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