rust/tests/ui/fn/issue-39259.stderr
bors 1d52972dd8 Auto merge of #125778 - estebank:issue-67100, r=compiler-errors
Use parenthetical notation for `Fn` traits

Always use the `Fn(T) -> R` format when printing closure traits instead of `Fn<(T,), Output = R>`.

Address #67100:

```
error[E0277]: expected a `Fn()` closure, found `F`
 --> file.rs:6:13
  |
6 |     call_fn(f)
  |     ------- ^ expected an `Fn()` closure, found `F`
  |     |
  |     required by a bound introduced by this call
  |
  = note: wrap the `F` in a closure with no arguments: `|| { /* code */ }`
note: required by a bound in `call_fn`
 --> file.rs:1:15
  |
1 | fn call_fn<F: Fn() -> ()>(f: &F) {
  |               ^^^^^^^^^^ required by this bound in `call_fn`
help: consider further restricting this bound
  |
5 | fn call_any<F: std::any::Any + Fn()>(f: &F) {
  |                              ++++++
```
2024-06-03 08:14:03 +00:00

35 lines
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error[E0229]: associated item constraints are not allowed here
--> $DIR/issue-39259.rs:6:17
|
LL | impl Fn(u32) -> u32 for S {
| ^^^ associated item constraint not allowed here
|
help: parenthesized trait syntax expands to `Fn<(u32,), Output=u32>`
--> $DIR/issue-39259.rs:6:6
|
LL | impl Fn(u32) -> u32 for S {
| ^^^^^^^^^^^^^^
error[E0277]: expected a `FnMut(u32)` closure, found `S`
--> $DIR/issue-39259.rs:6:25
|
LL | impl Fn(u32) -> u32 for S {
| ^ expected an `FnMut(u32)` closure, found `S`
|
= help: the trait `FnMut(u32)` is not implemented for `S`
note: required by a bound in `Fn`
--> $SRC_DIR/core/src/ops/function.rs:LL:COL
error[E0050]: method `call` has 1 parameter but the declaration in trait `call` has 2
--> $DIR/issue-39259.rs:9:13
|
LL | fn call(&self) -> u32 {
| ^^^^^ expected 2 parameters, found 1
|
= note: `call` from trait: `extern "rust-call" fn(&Self, Args) -> <Self as FnOnce<Args>>::Output`
error: aborting due to 3 previous errors
Some errors have detailed explanations: E0050, E0229, E0277.
For more information about an error, try `rustc --explain E0050`.