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