| error[E0596]: cannot borrow data in an index of `Container` as mutable | |
| --> $DIR/issue-44405.rs:21:5 | |
| | | |
| LL | container[&mut val].test(); | |
| | ^^^^^^^^^^^^^^^^^^^ cannot borrow as mutable | |
| | | |
| = help: trait `IndexMut` is required to modify indexed content, but it is not implemented for `Container` | |
| error: aborting due to previous error | |
| For more information about this error, try `rustc --explain E0596`. |