rust/src/test/ui/issues/issue-1460.stderr

warning: unused closure that must be used
  --> $DIR/issue-1460.rs:6:5
   |
LL |     {|i: u32| if 1 == i { }};
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: `#[warn(unused_must_use)]` on by default
   = note: closures are lazy and do nothing unless called

warning: 1 warning emitted
Make closures and generators a must use types Warn about unused expressions with closure or generator type. This follows existing precedence of must use annotations present on `FnOnce`, `FnMut`, `Fn` traits, which already indirectly apply to closures in some cases, e.g.,: ```rust fn f() -> impl FnOnce() { \|\| {} } fn main() { // an existing warning: unused implementer of `std::ops::FnOnce` that must be used: f(); // a new warning: unused closure that must be used: \|\| {}; } ``` 2020-07-28 00:00:00 +00:00			`warning: unused closure that must be used`
			`--> $DIR/issue-1460.rs:6:5`
			`\|`
			`LL \| {\|i: u32\| if 1 == i { }};`
			`\| ^^^^^^^^^^^^^^^^^^^^^^^^^`
			`\|`
			= note: `#[warn(unused_must_use)]` on by default
			`= note: closures are lazy and do nothing unless called`

			`warning: 1 warning emitted`