rust/library/core
Josh Stone b362958453 Add function core::iter::zip
This makes it a little easier to `zip` iterators:

```rust
for (x, y) in zip(xs, ys) {}
// vs.
for (x, y) in xs.into_iter().zip(ys) {}
```

You can `zip(&mut xs, &ys)` for the conventional `iter_mut()` and
`iter()`, respectively. This can also support arbitrary nesting, where
it's easier to see the item layout than with arbitrary `zip` chains:

```rust
for ((x, y), z) in zip(zip(xs, ys), zs) {}
for (x, (y, z)) in zip(xs, zip(ys, zs)) {}
// vs.
for ((x, y), z) in xs.into_iter().zip(ys).zip(xz) {}
for (x, (y, z)) in xs.into_iter().zip((ys.into_iter().zip(xz)) {}
```

It may also format more nicely, especially when the first iterator is a
longer chain of methods -- for example:

```rust
    iter::zip(
        trait_ref.substs.types().skip(1),
        impl_trait_ref.substs.types().skip(1),
    )
    // vs.
    trait_ref
        .substs
        .types()
        .skip(1)
        .zip(impl_trait_ref.substs.types().skip(1))
```

This replaces the tuple-pair `IntoIterator` in rust-lang/rust#78204.
There is prior art for the utility of this in [`itertools::zip`].

[`itertools::zip`]: https://docs.rs/itertools/0.10.0/itertools/fn.zip.html
2021-03-26 09:32:10 -07:00
..
benches Auto merge of #81358 - mcastorina:to-upper-lower-speed, r=joshtriplett 2021-03-17 11:17:18 +00:00
src Add function core::iter::zip 2021-03-26 09:32:10 -07:00
tests Auto merge of #82565 - m-ou-se:ununstabilize-bits, r=kennytm 2021-03-25 10:29:58 +00:00
Cargo.toml Auto merge of #82271 - Aaron1011:debug-refcell, r=m-ou-se 2021-03-23 04:49:47 +00:00