mirror of
https://github.com/rust-lang/rust.git
synced 2024-12-11 08:05:12 +00:00
67 lines
2.8 KiB
Plaintext
67 lines
2.8 KiB
Plaintext
error: `Iterator::map` call that discard the iterator's values
|
|
--> $DIR/lint_map_unit_fn.rs:9:18
|
|
|
|
|
LL | fn foo(items: &mut Vec<u8>) {
|
|
| --------------------------- this function returns `()`, which is likely not what you wanted
|
|
...
|
|
LL | x.iter_mut().map(foo);
|
|
| ^^^^---^
|
|
| | |
|
|
| | called `Iterator::map` with callable that returns `()`
|
|
| after this call to map, the resulting iterator is `impl Iterator<Item = ()>`, which means the only information carried by the iterator is the number of items
|
|
|
|
|
= note: `Iterator::map`, like many of the methods on `Iterator`, gets executed lazily, meaning that its effects won't be visible until it is iterated
|
|
note: the lint level is defined here
|
|
--> $DIR/lint_map_unit_fn.rs:1:9
|
|
|
|
|
LL | #![deny(map_unit_fn)]
|
|
| ^^^^^^^^^^^
|
|
help: you might have meant to use `Iterator::for_each`
|
|
|
|
|
LL | x.iter_mut().for_each(foo);
|
|
| ~~~~~~~~
|
|
|
|
error: `Iterator::map` call that discard the iterator's values
|
|
--> $DIR/lint_map_unit_fn.rs:11:18
|
|
|
|
|
LL | x.iter_mut().map(|items| {
|
|
| ^ -------
|
|
| | |
|
|
| ____________________|___this function returns `()`, which is likely not what you wanted
|
|
| | __________________|
|
|
| | |
|
|
LL | | |
|
|
LL | | | items.sort();
|
|
LL | | | });
|
|
| | | -^ after this call to map, the resulting iterator is `impl Iterator<Item = ()>`, which means the only information carried by the iterator is the number of items
|
|
| | |_____||
|
|
| |_______|
|
|
| called `Iterator::map` with callable that returns `()`
|
|
|
|
|
= note: `Iterator::map`, like many of the methods on `Iterator`, gets executed lazily, meaning that its effects won't be visible until it is iterated
|
|
help: you might have meant to use `Iterator::for_each`
|
|
|
|
|
LL | x.iter_mut().for_each(|items| {
|
|
| ~~~~~~~~
|
|
|
|
error: `Iterator::map` call that discard the iterator's values
|
|
--> $DIR/lint_map_unit_fn.rs:18:18
|
|
|
|
|
LL | let f = |items: &mut Vec<u8>| {
|
|
| --------------------- this function returns `()`, which is likely not what you wanted
|
|
...
|
|
LL | x.iter_mut().map(f);
|
|
| ^^^^-^
|
|
| | |
|
|
| | called `Iterator::map` with callable that returns `()`
|
|
| after this call to map, the resulting iterator is `impl Iterator<Item = ()>`, which means the only information carried by the iterator is the number of items
|
|
|
|
|
= note: `Iterator::map`, like many of the methods on `Iterator`, gets executed lazily, meaning that its effects won't be visible until it is iterated
|
|
help: you might have meant to use `Iterator::for_each`
|
|
|
|
|
LL | x.iter_mut().for_each(f);
|
|
| ~~~~~~~~
|
|
|
|
error: aborting due to 3 previous errors
|
|
|