Jacob Pratt 221dab89b4 Rollup merge of #139690 - cuviper:iter_repeat_n_default, r=tgross35 ...

`impl Default for RepeatN`

This creates an empty iterator, like `repeat_n(value, 0)` but without
needing any such value at hand. There's precedent in many other
iterators that the `Default` is empty, like `slice::Iter`.

I found myself wanting this for rayon's `RepeatN` as it lowers to a
sequential iterator [here][1]. Since rayon is also optimizing to avoid
extra clones, it may end up with parallel splits that have count 0 and
no item value. Calling `std::iter::repeat_n(x, 0)` just drops that
value, but there's no way to construct the same result without a value
yet. This would be straightforward with an empty `Default`.

[1]: https://github.com/rayon-rs/rayon/blob/ae07384e3e0b238cea89f0c14891f351c65a5cee/src/iter/repeat.rs#L201-L202

r? libs-api (insta-stable)

2026-04-18 00:05:16 -04:00

..

benches

Add missing num_internals feature gate to coretests/benches

2026-03-20 12:21:24 +01:00

tests

Rollup merge of #139690 - cuviper:iter_repeat_n_default, r=tgross35

2026-04-18 00:05:16 -04:00

Cargo.toml

Move float tests from std to core

2025-05-13 22:22:15 +00:00

lib.rs

Put all coretests in a separate crate

2025-01-26 10:26:36 +00:00