Add for_each_with
#367
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Add for_each_with
#367
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I had considered this method when adding `map_with` and `fold_with`, but at the time I decided it wasn't "primitive" enough. It is literally just `map_with(...).for_each(no-op)`. But we already have a user asking the best way to drive a void `map_with`, so it may be useful to provide.
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👍 I really wish we had |
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Regarding sequential iterators, I only found rust-lang/rust#14911, where the argument against seems mostly just that plain |
cuviper
referenced
this pull request
in cuviper/rust
Jun 20, 2017
This works like a `for` loop in functional style, applying a closure to every item in the `Iterator`. It doesn't allow `break`/`continue` like a `for` loop, nor any other control flow outside the closure, but it may be a more legible style for tying up the end of a long iterator chain. This was tried before in rust-lang#14911, but nobody made the case for using it with longer iterators. There was also `Iterator::advance` at that time which was more capable than `for_each`, but that no longer exists. The `itertools` crate has `Itertools::foreach` with the same behavior, but thankfully the names won't collide. The `rayon` crate also has a `ParallelIterator::for_each` where simple `for` loops aren't possible. > I really wish we had `for_each` on seq iterators. Having to use a > dummy operation is annoying. - [@nikomatsakis][1] [1]: https://github.com/nikomatsakis/rayon/pull/367#issuecomment-308455185
bors
referenced
this pull request
in rust-lang/rust
Jun 30, 2017
Add `Iterator::for_each` This works like a `for` loop in functional style, applying a closure to every item in the `Iterator`. It doesn't allow `break`/`continue` like a `for` loop, nor any other control flow outside the closure, but it may be a more legible style for tying up the end of a long iterator chain. This was tried before in #14911, but nobody made the case for using it with longer iterators. There was also `Iterator::advance` at that time which was more capable than `for_each`, but that no longer exists. The `itertools` crate has `Itertools::foreach` with the same behavior, but thankfully the names won't collide. The `rayon` crate also has a `ParallelIterator::for_each` where simple `for` loops aren't possible. > I really wish we had `for_each` on seq iterators. Having to use a > dummy operation is annoying. - [@nikomatsakis][1] [1]: https://github.com/nikomatsakis/rayon/pull/367#issuecomment-308455185
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I had considered this method when adding
map_withandfold_with, butat the time I decided it wasn't "primitive" enough. It is literally
just
map_with(...).for_each(no-op). But we already have a user askingthe best way to drive a void
map_with, so it may be useful to provide.cc #365