| # Freezing |
| |
| When data is bound by the same name immutably, it also *freezes*. *Frozen* data can't be |
| modified until the immutable binding goes out of scope: |
| |
| ```rust,editable,ignore,mdbook-runnable |
| fn main() { |
| let mut _mutable_integer = 7i32; |
| |
| { |
| // Shadowing by immutable `_mutable_integer` |
| let _mutable_integer = _mutable_integer; |
| |
| // Error! `_mutable_integer` is frozen in this scope |
| _mutable_integer = 50; |
| // FIXME ^ Comment out this line |
| |
| // `_mutable_integer` goes out of scope |
| } |
| |
| // Ok! `_mutable_integer` is not frozen in this scope |
| _mutable_integer = 3; |
| } |
| ``` |
