rust/library/core
bors 0c9ef564a7 Auto merge of #79656 - jnqnfe:ordering, r=sfackler
Add some core::cmp::Ordering helpers

...to allow easier equal-to-or-greater-than and less-than-or-equal-to
comparisons.

Prior to Rust 1.42 a greater-than-or-equal-to comparison might be written
either as a match block, or a traditional conditional check like this:

```rust
if cmp == Ordering::Equal || cmp == Ordering::Greater {
    // Do something
}
```

Which requires two instances of `cmp`. Don't forget that while `cmp` here
is very short, it could be something much longer in real use cases.

From Rust 1.42 a nicer alternative is possible:

```rust
if matches!(cmp, Ordering::Equal | Ordering::Greater) {
    // Do something
}
```

The commit adds another alternative which may be even better in some cases:

```rust
if cmp.is_equal_or_greater() {
    // Do something
}
```

The earlier examples could be cleaner than they are if the variants of
`Ordering` are imported such that `Equal`, `Greater` and `Less` can be
referred to directly, but not everyone will want to do that.

The new solution can shorten lines, help avoid logic mistakes, and avoids
having to import `Ordering` / `Ordering::*`.
2020-12-11 03:08:32 +00:00
..
benches Remove redundant 'static from library crates 2020-10-18 17:25:51 +02:00
src Auto merge of #79656 - jnqnfe:ordering, r=sfackler 2020-12-11 03:08:32 +00:00
tests Remove unused feature gate 2020-12-06 22:29:13 +01:00
Cargo.toml mv std libs to library/ 2020-07-27 19:51:13 -05:00