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``` 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; | + ```
80 lines
2.7 KiB
Plaintext
80 lines
2.7 KiB
Plaintext
error[E0502]: cannot borrow `*list` as mutable because it is also borrowed as immutable
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--> $DIR/clone-on-ref.rs:7:5
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LL | for v in list.iter() {
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| ---- immutable borrow occurs here
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LL | cloned_items.push(v.clone())
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| ------- this call doesn't do anything, the result is still `&T` because `T` doesn't implement `Clone`
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LL | }
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LL | list.push(T::default());
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| ^^^^^^^^^^^^^^^^^^^^^^^ mutable borrow occurs here
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LL |
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LL | drop(cloned_items);
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| ------------ immutable borrow later used here
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help: consider further restricting this bound
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LL | fn foo<T: Default + Clone>(list: &mut Vec<T>) {
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| +++++++
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error[E0505]: cannot move out of `x` because it is borrowed
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--> $DIR/clone-on-ref.rs:14:10
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LL | fn bar<T: std::fmt::Display>(x: T) {
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| - binding `x` declared here
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LL | let a = &x;
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| -- borrow of `x` occurs here
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LL | let b = a.clone();
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| ------- this call doesn't do anything, the result is still `&T` because `T` doesn't implement `Clone`
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LL | drop(x);
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| ^ move out of `x` occurs here
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LL |
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LL | println!("{b}");
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| --- borrow later used here
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help: if `T` implemented `Clone`, you could clone the value
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--> $DIR/clone-on-ref.rs:11:8
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LL | fn bar<T: std::fmt::Display>(x: T) {
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| ^ consider constraining this type parameter with `Clone`
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LL | let a = &x;
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| -- you could clone this value
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help: consider further restricting this bound
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LL | fn bar<T: std::fmt::Display + Clone>(x: T) {
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| +++++++
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error[E0505]: cannot move out of `x` because it is borrowed
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--> $DIR/clone-on-ref.rs:23:10
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LL | fn qux(x: A) {
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| - binding `x` declared here
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LL | let a = &x;
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| -- borrow of `x` occurs here
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LL | let b = a.clone();
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| ------- this call doesn't do anything, the result is still `&A` because `A` doesn't implement `Clone`
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LL | drop(x);
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| ^ move out of `x` occurs here
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LL |
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LL | println!("{b:?}");
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| ----- borrow later used here
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note: if `A` implemented `Clone`, you could clone the value
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--> $DIR/clone-on-ref.rs:19:1
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LL | struct A;
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| ^^^^^^^^ consider implementing `Clone` for this type
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LL | fn qux(x: A) {
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LL | let a = &x;
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| -- you could clone this value
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help: consider annotating `A` with `#[derive(Clone)]`
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LL + #[derive(Clone)]
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LL | struct A;
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error: aborting due to 3 previous errors
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Some errors have detailed explanations: E0502, E0505.
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For more information about an error, try `rustc --explain E0502`.
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