This reverts commit 7f1d1c6d9a7be5e427bace30e740b16b25f25c92.
The original commit was created because mdBook and rustdoc had
different generation algorithms for header links; now with
https://github.com/rust-lang/rust/pull/39966 , the algorithms
are the same. So let's undo this change.
... when I came across this problem, I said "eh, this isn't fun,
but it doesn't take that long." I probably should have just actually
taken the time to fix upstream, given that they were amenable. Oh
well!
Allow more Cell methods for non-Copy types
Clearly, `get_mut` is safe for any `T`. The other two only provide unsafe pointers anyway.
The only remaining inherent method with `Copy` bound is `get`, which sounds about right to me.
I found the order if `impl` blocks in the file a little weird (first inherent impl, then some trait impls, then another inherent impl), but didn't change it to keep the diff small.
Contributes to #39264
Port books to mdbook
Part of https://github.com/rust-lang/rust/issues/39588
blocked on https://github.com/rust-lang/rust/pull/39431
As a first step towards the bookshelf, we ~vendor mdbook in-tree and~ port our books to it. Eventually, both of these books will be moved out-of-tree, but the nightly book will rely on doing the same thing. As such, this intermediate step is useful.
r? @alexcrichton @brson
/cc @azerupi
Add PartialOrd, Ord derivations to TypeId
I want to be able to sort a `Vec` of types which contain `TypeId`s, so an `Ord` derivation would be very useful to me. `Hash` and `PartialEq`/`Eq` already exist, so the missing `PartialOrd` and `Ord` derivations feel like an oversight to me.
improve error message when two-arg assert_eq! receives a trailing comma
Previously, `assert_eq!(left, right,)` (respectively, `assert_ne!(left,
right,)`; note the trailing comma) would result in a confusing "requires
at least a format string argument" error. In reality, a format string is
optional, but the trailing comma puts us into the "match a token tree of
zero or more tokens" branch of the macro (in order to support the
optional format string), and passing the empty token tree into
`format_args!` results in the confusing error. If instead we match a
token tree of one or more tokens, we get a much more sensible
"unexpected end of macro invocation" error.
While we're here, fix up a stray space before a comma in the match
guards.
Resolves#39369.
-----
**Before:**
```
$ rustc scratch.rs
error: requires at least a format string argument
--> scratch.rs:2:5
|
2 | assert_eq!(1, 2,);
| ^^^^^^^^^^^^^^^^^^
|
= note: this error originates in a macro outside of the current crate
error: aborting due to previous error
```
**After:**
```
$ ./build/x86_64-unknown-linux-gnu/stage1/bin/rustc scratch.rs
error: unexpected end of macro invocation
--> scratch.rs:2:20
|
2 | assert_eq!(1, 2,);
| ^
```
Fix a misleading statement in `Iterator.nth()`
The `Iterator.nth()` documentation says "Note that all preceding elements will be consumed". I assumed from that that the preceding elements would be the *only* ones that were consumed, but in fact the returned element is consumed as well.
The way I read the documentation, I assumed that `nth(0)` would not discard anything (there are 0 preceding elements, and maybe it just peeks at the start of the iterator somehow), so I added a sentence clarifying that it does. I also rephrased it to avoid the stunted "i.e." phrasing.
Specialize `PartialOrd<A> for [A] where A: Ord`
This way we can call `cmp` instead of `partial_cmp` in the loop, removing some burden of optimizing `Option`s away from the compiler.
PR #39538 introduced a regression where sorting slices suddenly became slower, since `slice1.lt(slice2)` was much slower than `slice1.cmp(slice2) == Less`. This problem is now fixed.
To verify, I benchmarked this simple program:
```rust
fn main() {
let mut v = (0..2_000_000).map(|x| x * x * x * 18913515181).map(|x| vec![x, x ^ 3137831591]).collect::<Vec<_>>();
v.sort();
}
```
Before this PR, it would take 0.95 sec, and now it takes 0.58 sec.
I also tried changing the `is_less` lambda to use `cmp` and `partial_cmp`. Now all three versions (`lt`, `cmp`, `partial_cmp`) are equally performant for sorting slices - all of them take 0.58 sec on the
benchmark.
Tangentially, as soon as we get `default impl`, it might be a good idea to implement a blanket default impl for `lt`, `gt`, `le`, `ge` in terms of `cmp` whenever possible. Today, those four functions by default are only implemented in terms of `partial_cmp`.
r? @alexcrichton
The `Iterator.nth()` documentation says "Note that all preceding elements will be consumed". I assumed from that that the preceding elements would be the *only* ones that were consumed, but in fact the returned element is consumed as well.
The way I read the documentation, I assumed that `nth(0)` would not discard anything (as there are 0 preceding elements), so I added a sentence clarifying that it does. I also rephrased it to avoid the stunted "i.e." phrasing.
Improve format float
* Move float into mod float like in test
* Add more tests for f64 f32, lower exp, upper exp, which can come if handy in the future if we want refactor further
* Use `assert_eq` for clearer error messages
This way we can call `cmp` instead of `partial_cmp` in the loop,
removing some burden of optimizing `Option`s away from the compiler.
PR #39538 introduced a regression where sorting slices suddenly became
slower, since `slice1.lt(slice2)` was much slower than
`slice1.cmp(slice2) == Less`. This problem is now fixed.
To verify, I benchmarked this simple program:
```rust
fn main() {
let mut v = (0..2_000_000).map(|x| x * x * x * 18913515181).map(|x| vec![x, x ^ 3137831591]).collect::<Vec<_>>();
v.sort();
}
```
Before this PR, it would take 0.95 sec, and now it takes 0.58 sec.
I also tried changing the `is_less` lambda to use `cmp` and
`partial_cmp`. Now all three versions (`lt`, `cmp`, `partial_cmp`) are
equally performant for sorting slices - all of them take 0.58 sec on the
benchmark.
Previously, `assert_eq!(left, right,)` (respectively, `assert_ne!(left,
right,)`; note the trailing comma) would result in a confusing "requires
at least a format string argument" error. In reality, a format string is
optional, but the trailing comma puts us into the "match a token tree of
zero or more tokens" branch of the macro (in order to support the
optional format string), and passing the empty token tree into
`format_args!` results in the confusing error. If instead we match a
token tree of one or more tokens, we get a much more sensible
"unexpected end of macro invocation" error.
While we're here, fix up a stray space before a comma in the match
guards.
Resolves#39369.
Fix TryFrom for i128/u128
Another case of `as` cast silent truncation being error prone.
This also adds a few missing TryFrom tests to libcoretest.
cc #33417
cc #35118
Add a name for the parameter to `TryFrom::try_from`.
Although signatures with anonymous parameters may not be deprecated or removed at this point, the team seems to agree that the ability to have an anonymous parameter is unfortunate historical baggage, and that we shouldn't create new code that uses it.
Context: https://github.com/rust-lang/rust/issues/33417#issuecomment-276933861
Provide Entry-like API for Option
This implements #39288.
I am wondering whether to use std::intrinsics::unreachable!() here. Both seems fine to me (the second match optimizes away in release mode).
branchless .filter(_).count()
I found that the branchless version is only slower if we have little to no branch misses, which usually isn't the case. I notice speedups between -5% (perfect prediction) and 60% (real world data).
Add 128-bit atomics
This is currently only supported on AArch64 since that is the only target which unconditionally supports 128-bit atomic operations.
cc #35118
Bump version, upgrade bootstrap
This commit updates the version number to 1.17.0 as we're not on that version of
the nightly compiler, and at the same time this updates src/stage0.txt to
bootstrap from freshly minted beta compiler and beta Cargo.
This commit updates the version number to 1.17.0 as we're not on that version of
the nightly compiler, and at the same time this updates src/stage0.txt to
bootstrap from freshly minted beta compiler and beta Cargo.
