|
|
|
|
|
|
by ben0x539
3392 days ago
|
|
|
`FnMut` just means that the iterator methods don't artificially restrict the user-supplied closures. `map` itself doesn't become impure just because you can map `|x| { counter += x; x+1 }` over your list if you really want to. I think it's fair to say that iterator methods are typically used as combinators to build computations out of pure functions to avoid having to manage mutable state. |
|
|