mirror of https://github.com/rust-lang/rust
24 lines
1022 B
Plaintext
24 lines
1022 B
Plaintext
error: `Iterator::map` call that discard the iterator's values
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--> $DIR/issue-109152.rs:5:21
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LL | vec![42].iter().map(drop);
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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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| | 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/issue-109152.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 | vec![42].iter().for_each(drop);
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| ~~~~~~~~
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error: aborting due to 1 previous error
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