rust/tests/ui/moves/borrow-closures-instead-of-move.stderr
Esteban Küber d68f2a6b71 Mention when type parameter could be Clone
```
error[E0382]: use of moved value: `t`
  --> $DIR/use_of_moved_value_copy_suggestions.rs:7:9
   |
LL | fn duplicate_t<T>(t: T) -> (T, T) {
   |                   - move occurs because `t` has type `T`, which does not implement the `Copy` trait
...
LL |     (t, t)
   |      -  ^ value used here after move
   |      |
   |      value moved here
   |
help: if `T` implemented `Clone`, you could clone the value
  --> $DIR/use_of_moved_value_copy_suggestions.rs:4:16
   |
LL | fn duplicate_t<T>(t: T) -> (T, T) {
   |                ^ consider constraining this type parameter with `Clone`
...
LL |     (t, t)
   |      - you could clone this value
help: consider restricting type parameter `T`
   |
LL | fn duplicate_t<T: Copy>(t: T) -> (T, T) {
   |                 ++++++
```

The `help` is new. On ADTs, we also extend the output with span labels:

```
error[E0507]: cannot move out of static item `FOO`
  --> $DIR/issue-17718-static-move.rs:6:14
   |
LL |     let _a = FOO;
   |              ^^^ move occurs because `FOO` has type `Foo`, which does not implement the `Copy` trait
   |
note: if `Foo` implemented `Clone`, you could clone the value
  --> $DIR/issue-17718-static-move.rs:1:1
   |
LL | struct Foo;
   | ^^^^^^^^^^ consider implementing `Clone` for this type
...
LL |     let _a = FOO;
   |              --- you could clone this value
help: consider borrowing here
   |
LL |     let _a = &FOO;
   |              +
```
2024-04-24 22:21:15 +00:00

85 lines
3 KiB
Plaintext

error[E0382]: use of moved value: `f`
--> $DIR/borrow-closures-instead-of-move.rs:3:22
|
LL | fn takes_fn(f: impl Fn()) {
| - move occurs because `f` has type `impl Fn()`, which does not implement the `Copy` trait
LL | loop {
| ---- inside of this loop
LL | takes_fnonce(f);
| ^ value moved here, in previous iteration of loop
|
note: consider changing this parameter type in function `takes_fnonce` to borrow instead if owning the value isn't necessary
--> $DIR/borrow-closures-instead-of-move.rs:34:20
|
LL | fn takes_fnonce(_: impl FnOnce()) {}
| ------------ ^^^^^^^^^^^^^ this parameter takes ownership of the value
| |
| in this function
help: if `impl Fn()` implemented `Clone`, you could clone the value
--> $DIR/borrow-closures-instead-of-move.rs:1:16
|
LL | fn takes_fn(f: impl Fn()) {
| ^^^^^^^^^ consider constraining this type parameter with `Clone`
LL | loop {
LL | takes_fnonce(f);
| - you could clone this value
help: consider borrowing `f`
|
LL | takes_fnonce(&f);
| +
error[E0382]: use of moved value: `m`
--> $DIR/borrow-closures-instead-of-move.rs:14:18
|
LL | fn takes_fn_mut(m: impl FnMut()) {
| - move occurs because `m` has type `impl FnMut()`, which does not implement the `Copy` trait
LL | if maybe() {
LL | takes_fnonce(m);
| - value moved here
...
LL | takes_fnonce(m);
| ^ value used here after move
|
note: consider changing this parameter type in function `takes_fnonce` to borrow instead if owning the value isn't necessary
--> $DIR/borrow-closures-instead-of-move.rs:34:20
|
LL | fn takes_fnonce(_: impl FnOnce()) {}
| ------------ ^^^^^^^^^^^^^ this parameter takes ownership of the value
| |
| in this function
help: if `impl FnMut()` implemented `Clone`, you could clone the value
--> $DIR/borrow-closures-instead-of-move.rs:9:20
|
LL | fn takes_fn_mut(m: impl FnMut()) {
| ^^^^^^^^^^^^ consider constraining this type parameter with `Clone`
LL | if maybe() {
LL | takes_fnonce(m);
| - you could clone this value
help: consider mutably borrowing `m`
|
LL | takes_fnonce(&mut m);
| ++++
error[E0382]: borrow of moved value: `closure`
--> $DIR/borrow-closures-instead-of-move.rs:25:5
|
LL | takes_fnonce(closure);
| ------- value moved here
LL |
LL | closure();
| ^^^^^^^ value borrowed here after move
|
note: closure cannot be moved more than once as it is not `Copy` due to moving the variable `x` out of its environment
--> $DIR/borrow-closures-instead-of-move.rs:21:9
|
LL | x += 1;
| ^
help: consider mutably borrowing `closure`
|
LL | takes_fnonce(&mut closure);
| ++++
error: aborting due to 3 previous errors
For more information about this error, try `rustc --explain E0382`.