// Test that we can derive lifetime bounds on type parameters // from trait inheritance. trait Static : 'static { } trait Is<'a> : 'a { } struct Inv<'a> { x: Option<&'a mut &'a isize> } fn check_bound<'a,A:'a>(x: Inv<'a>, a: A) { } // In all of these cases, we can derive a bound for A that is longer // than 'a based on the trait bound of A: fn foo1<'a,A:Static>(x: Inv<'a>, a: A) { check_bound(x, a) } fn foo2<'a,A:Static>(x: Inv<'static>, a: A) { check_bound(x, a) } fn foo3<'a,A:Is<'a>>(x: Inv<'a>, a: A) { check_bound(x, a) } // In these cases, there is no trait bound, so we cannot derive any // bound for A and we get an error: fn bar1<'a,A>(x: Inv<'a>, a: A) { check_bound(x, a) //~ ERROR parameter type `A` may not live long enough } fn bar2<'a,'b,A:Is<'b>>(x: Inv<'a>, y: Inv<'b>, a: A) { check_bound(x, a) //~ ERROR parameter type `A` may not live long enough } fn main() { }