rust/tests/ui/btreemap/btreemap-index-mut.stderr
2023-01-11 09:32:08 +00:00

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error[E0594]: cannot assign to data in an index of `BTreeMap<u32, u32>`
--> $DIR/btreemap-index-mut.rs:5:5
|
LL | map[&0] = 1;
| ^^^^^^^^^^^ cannot assign
|
= help: trait `IndexMut` is required to modify indexed content, but it is not implemented for `BTreeMap<u32, u32>`
help: to modify a `BTreeMap<u32, u32>`, use `.get_mut()`, `.insert()` or the entry API
|
LL | map.insert(&0, 1);
| ~~~~~~~~ ~ +
LL | map.get_mut(&0).map(|val| { *val = 1; });
| ~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ ++++
LL | let val = map.entry(&0).or_insert(1);
| +++++++++ ~~~~~~~ ~~~~~~~~~~~~ +
error: aborting due to previous error
For more information about this error, try `rustc --explain E0594`.