1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
|
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: use `.insert()` to insert a value into a `BTreeMap<u32, u32>`, `.get_mut()` to modify it, or the entry API for more flexibility
|
LL | map.insert(&0, 1);
| ~~~~~~~~ ~ +
LL | if let Some(val) = map.get_mut(&0) { *val = 1; };
| ++++++++++++++++++ ~~~~~~~~~ ~~~~~~~~ +++
LL | let val = map.entry(&0).or_insert(1);
| +++++++++ ~~~~~~~ ~~~~~~~~~~~~ +
error: aborting due to 1 previous error
For more information about this error, try `rustc --explain E0594`.
|