//! Checks the correct usage and behavior of the anonymous lifetime `'_` (underscore lifetime) //@ run-pass #![allow(dead_code, mismatched_lifetime_syntaxes)] struct Foo<'a>(&'a u8); fn foo(x: &u8) -> Foo<'_> { Foo(x) } fn foo2(x: &'_ u8) -> Foo<'_> { Foo(x) } fn foo3(x: &'_ u8) -> Foo { Foo(x) } fn foo4(_: Foo<'_>) {} struct Foo2<'a, 'b> { a: &'a u8, b: &'b u8, } fn foo5<'b>(foo: Foo2<'_, 'b>) -> &'b u8 { foo.b } fn main() { let x = &5; let _ = foo(x); let _ = foo2(x); let _ = foo3(x); foo4(Foo(x)); let _ = foo5(Foo2 { a: x, b: &6 }); }