821d50aa0c
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:
|| {};
}
```
|
||
|---|---|---|
| .. | ||
| unused-attr.rs | ||
| unused-attr.stderr | ||
| unused-closure.rs | ||
| unused-closure.stderr | ||
| unused-macro-rules.rs | ||
| unused-macro-rules.stderr | ||
| unused-macro-with-bad-frag-spec.rs | ||
| unused-macro-with-bad-frag-spec.stderr | ||
| unused-macro-with-follow-violation.rs | ||
| unused-macro-with-follow-violation.stderr | ||
| unused-macro.rs | ||
| unused-macro.stderr | ||
| unused-mut-warning-captured-var.fixed | ||
| unused-mut-warning-captured-var.rs | ||
| unused-mut-warning-captured-var.stderr | ||
| unused-result.rs | ||
| unused-result.stderr | ||