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|
error[E0070]: invalid left-hand side of assignment
--> $DIR/assign-non-lval-derefmut.rs:5:23
|
LL | x.lock().unwrap() = 2;
| ----------------- ^
| |
| cannot assign to this expression
|
help: consider dereferencing here to assign to the mutably borrowed value
|
LL | *x.lock().unwrap() = 2;
| +
error[E0368]: binary assignment operation `+=` cannot be applied to type `MutexGuard<'_, usize>`
--> $DIR/assign-non-lval-derefmut.rs:7:5
|
LL | x.lock().unwrap() += 1;
| -----------------^^^^^
| |
| cannot use `+=` on type `MutexGuard<'_, usize>`
|
note: the foreign item type `MutexGuard<'_, usize>` doesn't implement `AddAssign<{integer}>`
--> $SRC_DIR/std/src/sync/poison/mutex.rs:LL:COL
|
= note: not implement `AddAssign<{integer}>`
help: `+=` can be used on `usize` if you dereference the left-hand side
|
LL | *x.lock().unwrap() += 1;
| +
error[E0308]: mismatched types
--> $DIR/assign-non-lval-derefmut.rs:11:9
|
LL | let mut y = x.lock().unwrap();
| ----------------- expected due to this value
LL | y = 2;
| ^ expected `MutexGuard<'_, usize>`, found integer
|
= note: expected struct `MutexGuard<'_, usize>`
found type `{integer}`
help: consider dereferencing here to assign to the mutably borrowed value
|
LL | *y = 2;
| +
error[E0368]: binary assignment operation `+=` cannot be applied to type `MutexGuard<'_, usize>`
--> $DIR/assign-non-lval-derefmut.rs:13:5
|
LL | y += 1;
| -^^^^^
| |
| cannot use `+=` on type `MutexGuard<'_, usize>`
|
note: the foreign item type `MutexGuard<'_, usize>` doesn't implement `AddAssign<{integer}>`
--> $SRC_DIR/std/src/sync/poison/mutex.rs:LL:COL
|
= note: not implement `AddAssign<{integer}>`
help: `+=` can be used on `usize` if you dereference the left-hand side
|
LL | *y += 1;
| +
error: aborting due to 4 previous errors
Some errors have detailed explanations: E0070, E0308, E0368.
For more information about an error, try `rustc --explain E0070`.
|
