| #![deny(single_use_lifetimes)] |
| #![allow(dead_code)] |
| #![allow(unused_variables)] |
| |
| // Test that we DO warn when lifetime name is used only |
| // once in a fn argument. |
| |
| fn a<'a>(x: &'a u32) { //~ ERROR `'a` only used once |
| //~^ HELP elide the single-use lifetime |
| } |
| |
| struct Single<'a> { x: &'a u32 } |
| struct Double<'a, 'b> { f: &'a &'b u32 } |
| |
| fn center<'m>(_: Single<'m>) {} //~ ERROR `'m` only used once |
| //~^ HELP elide the single-use lifetime |
| fn left<'x, 'y>(foo: Double<'x, 'y>) -> &'x u32 { foo.f } //~ ERROR `'y` only used once |
| //~^ HELP elide the single-use lifetime |
| fn right<'x, 'y>(foo: Double<'x, 'y>) -> &'y u32 { foo.f } //~ ERROR `'x` only used once |
| //~^ HELP elide the single-use lifetime |
| |
| fn main() { } |