rust/tests/ui/regions/region-lifetime-bounds-on-fns-where-clause.rs

31 lines
888 B
Rust

fn a<'a, 'b>(x: &mut &'a isize, y: &mut &'b isize) where 'b: 'a {
// Note: this is legal because of the `'b:'a` declaration.
*x = *y;
}
fn b<'a, 'b>(x: &mut &'a isize, y: &mut &'b isize) {
// Illegal now because there is no `'b:'a` declaration.
*x = *y; //~ ERROR: lifetime may not live long enough
}
fn c<'a,'b>(x: &mut &'a isize, y: &mut &'b isize) {
// Here we try to call `foo` but do not know that `'a` and `'b` are
// related as required.
a(x, y); //~ ERROR: lifetime may not live long enough
}
fn d() {
// 'a and 'b are early bound in the function `a` because they appear
// inconstraints:
let _: fn(&mut &isize, &mut &isize) = a;
//~^ ERROR mismatched types [E0308]
}
fn e() {
// 'a and 'b are late bound in the function `b` because there are
// no constraints:
let _: fn(&mut &isize, &mut &isize) = b;
}
fn main() { }