Reduces Code Repetitions like `!n >> amt`
Fixes#49937 .
This PR contains defining a function which operates bit inversion and reducing bit operation like `!0u128 >> (128 - size.bits())`.
Fix#54822 and associated faulty tests
Type checking associated constants can require trait bounds, but an empty
parameter environment was provided to the trait solver. Providing an
appropriate parameter environment seems to fix#54822 and also make one of the
cases in src/test/ui/nll/trait-associated-constant.rs that should compile
successfully do so. It also (slightly) improves the error message in
src/test/ui/associated-const/associated-const-generic-obligations.rs
Standardize `Range*` documentation
This updates the final example in the documentation for the types
`Range`, `RangeFrom`, `RangeFull`, `RangeInclusive`, `RangeTo`,
`RangeToInclusive`.
Use lifetime contravariance to elide more lifetimes in core+alloc+std
Sample:
```diff
- impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b mut B> for &'a mut A where A: PartialEq<B> {
+ impl<A: ?Sized, B: ?Sized> PartialEq<&mut B> for &mut A where A: PartialEq<B> {
#[inline]
- fn eq(&self, other: &&'b mut B) -> bool { PartialEq::eq(*self, *other) }
+ fn eq(&self, other: &&mut B) -> bool { PartialEq::eq(*self, *other) }
#[inline]
- fn ne(&self, other: &&'b mut B) -> bool { PartialEq::ne(*self, *other) }
+ fn ne(&self, other: &&mut B) -> bool { PartialEq::ne(*self, *other) }
}
```
[I didn't know this worked](https://internals.rust-lang.org/t/why-can-you-use-different-unconstrained-lifetimes-to-implement-traits/9544/2?u=scottmcm) until recently, but since defining methods contravariantly in their lifetimes this way has worked back to Rust 1.0, we might as well take advantage of combining it with IHLE.
Fix documentation of from_ne_bytes and from_le_bytes
Copypasta mistake, the documentation of `from_ne_bytes` and `from_le_bytes` used the big-endian variant in the example snippets.
Expand docs for `TryFrom` and `TryInto`.
The examples are still lacking for now, both for module docs and for methods/impl's. Will be adding those in further pushes.
Should hopefully resolve the doc concern in #33417 when finished?
