mirror of https://github.com/rust-lang/rust
67 lines
2.8 KiB
Plaintext
67 lines
2.8 KiB
Plaintext
error: `Iterator::map` call that discard the iterator's values
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--> $DIR/lint_map_unit_fn.rs:9:18
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LL | fn foo(items: &mut Vec<u8>) {
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| --------------------------- this function returns `()`, which is likely not what you wanted
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...
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LL | x.iter_mut().map(foo);
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| ^^^^---^
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| | |
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| | called `Iterator::map` with callable that returns `()`
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| 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
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= 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
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note: the lint level is defined here
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--> $DIR/lint_map_unit_fn.rs:1:9
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LL | #![deny(map_unit_fn)]
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| ^^^^^^^^^^^
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help: you might have meant to use `Iterator::for_each`
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LL | x.iter_mut().for_each(foo);
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| ~~~~~~~~
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error: `Iterator::map` call that discard the iterator's values
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--> $DIR/lint_map_unit_fn.rs:11:18
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LL | x.iter_mut().map(|items| {
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| ^ -------
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| | |
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| ____________________|___this function returns `()`, which is likely not what you wanted
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| | __________________|
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| | |
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LL | | |
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LL | | | items.sort();
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LL | | | });
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| | | -^ 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
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| | |_____||
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| |_______|
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| called `Iterator::map` with callable that returns `()`
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= 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
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help: you might have meant to use `Iterator::for_each`
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LL | x.iter_mut().for_each(|items| {
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| ~~~~~~~~
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error: `Iterator::map` call that discard the iterator's values
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--> $DIR/lint_map_unit_fn.rs:18:18
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LL | let f = |items: &mut Vec<u8>| {
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| --------------------- this function returns `()`, which is likely not what you wanted
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...
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LL | x.iter_mut().map(f);
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| ^^^^-^
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| | |
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| | called `Iterator::map` with callable that returns `()`
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| 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
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= 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
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help: you might have meant to use `Iterator::for_each`
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LL | x.iter_mut().for_each(f);
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| ~~~~~~~~
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error: aborting due to 3 previous errors
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