Add contribution instructions to stdlib docs
Generally programming language docs have instructions on how to contribute changes.
I couldn't find any in the rust docs, so I figured I'd add an instructions section, let me know if this belongs somewhere else!
Reduce str transmutes, add mut versions of methods.
When I was working on the various parts involved in #40380 one of the comments I got was the excess of transmutes necessary to make the changes work. This is part of a set of multiple changes I'd like to offer to fix this problem.
I think that having these methods is reasonable because they're already possible via transmutes, and it makes the code that uses them safer. I can also add `pub(crate)` to these methods for now if the libs team would rather not expose them to the public without an RFC.
Update ChildStderr docs to be clearer
Before the docs only had a line about where it was found and that it was
a handle to stderr. This commit changes it so that the summary second line is
removed and that it's a bit clearer about what can be done with it. Part of
#29370
Fix Markdown issues in the docs
* Since the switch to pulldown-cmark reference links need a blank line
before the URLs. (#40912)
* Reference link references are not case sensitive.
* Doc comments need to be indented uniformly otherwise rustdoc gets
confused.
* Since the switch to pulldown-cmark reference links need a blank line
before the URLs.
* Reference link references are not case sensitive.
* Doc comments need to be indented uniformly otherwise rustdoc gets
confused.
std: Use `poll` instead of `select`
This gives us the benefit of supporting file descriptors over the limit that
select supports, which...
Closes#40894
Simplify HashMap Bucket interface
> Simplify HashMap Bucket interface
>
> * Store capacity_mask instead of capacity
> * Move bucket index into RawBucket
> * Valid bucket index is now always within [0..table_capacity)
> * Simplify iterators by moving logic into RawBuckets
> * Clone RawTable using RawBucket
> * Make retain aware of the number of elements
The idea was to put idx in RawBucket instead of the other Bucket types and simplify next() and prev() as much as possible. The rest was a side-effect of that change, except maybe the last 2.
This change makes iteration and other next/prev() heavy operations noticeably faster. Clone is way faster.
```
➜ hashmap2 git:(adapt) ✗ cargo benchcmp pre:: adp:: bench.txt
name pre:: ns/iter adp:: ns/iter diff ns/iter diff %
clone_10_000 74,364 39,736 -34,628 -46.57%
grow_100_000 8,343,553 8,233,785 -109,768 -1.32%
grow_10_000 817,825 723,958 -93,867 -11.48%
grow_big_value_100_000 18,418,979 17,906,186 -512,793 -2.78%
grow_big_value_10_000 1,219,242 1,103,334 -115,908 -9.51%
insert_1000 74,546 58,343 -16,203 -21.74%
insert_100_000 6,743,770 6,238,017 -505,753 -7.50%
insert_10_000 798,079 719,123 -78,956 -9.89%
insert_1_000_000 275,215,605 266,975,875 -8,239,730 -2.99%
insert_int_bigvalue_10_000 1,517,387 1,419,838 -97,549 -6.43%
insert_str_10_000 316,179 278,896 -37,283 -11.79%
insert_string_10_000 770,927 747,449 -23,478 -3.05%
iter_keys_100_000 386,099 333,104 -52,995 -13.73%
iterate_100_000 387,320 355,707 -31,613 -8.16%
lookup_100_000 206,757 193,063 -13,694 -6.62%
lookup_100_000_unif 219,366 193,180 -26,186 -11.94%
lookup_1_000_000 206,456 205,716 -740 -0.36%
lookup_1_000_000_unif 659,934 629,659 -30,275 -4.59%
lru_sim 20,194,334 18,442,149 -1,752,185 -8.68%
merge_shuffle 1,168,044 1,063,055 -104,989 -8.99%
```
Note 2: I may have messed up porting the diff, let's see what CI says.
Revert "Implement AsRawFd/IntoRawFd for RawFd"
This reverts commit 2cf686f2cd (#40842)
RawFd is a type alias for c_int, which is itself a type alias for i32.
As a result, adding AsRawFd and IntoRawFd impls for RawFd actually adds
them for i32.
As a result, the reverted commit makes this valid:
```
use std::os::unix::io::AsRawFd;
fn arf<T: AsRawFd>(_: T) {}
fn main() {
arf(32i32)
}
```
Implimenting AsRawFd and IntoRawFd for i32 breaks the promises of both
those traits that their methods return a valid RawFd.
r? @aturon
cc @Mic92 @kamalmarhubi
Add links and some examples to std::sync::mpsc docs
Addresses part of #29377
r? @steveklabnik
I took a stab at adding links to the `std::sync::mpsc` docs, and I also wrote a few examples.
Edit: Whoops, typed in `?r` instead of `r?`.
* Store capacity_mask instead of capacity
* Move bucket index into RawBucket
* Bucket index is now always within [0..table_capacity)
* Clone RawTable using RawBucket
* Simplify iterators by moving logic into RawBuckets
* Make retain aware of the number of elements
This reverts commit 2cf686f2cd (#40842)
RawFd is a type alias for c_int, which is itself a type alias for i32.
As a result, adding AsRawFd and IntoRawFd impls for RawFd actually adds
them for i32.
As a result, the reverted commit makes this valid:
```
use std::os::unix::io::AsRawFd;
fn arf<T: AsRawFd>(_: T) {}
fn main() {
arf(32i32)
}
```
Implimenting AsRawFd and IntoRawFd for i32 breaks the promises of both
those traits that their methods return a valid RawFd.
r? @aturon
cc @Mic92 @kamalmarhubi
* Change `utf8` variable names to `non_ascii` to be more clear, since
ASCII and UTF-8 are compatible.
* Fix `EscapeDefault` struct description to follow the typical iterator
method format with a link to the generating function.
* Add more `escape_default` examples to cover every case mentioned in
the function description itself.
Add helpful hint in io docs about how ? is not allowed in main()
This is my effort to help alleviate the confusion caused by the error message:
```rust
error[E0277]: the trait bound `(): std::ops::Carrier` is not satisfied
--> hello_world.rs:72:5
|
72 | io::stdin().read_line(&mut d_input)?;
| ------------------------------------
| |
| the trait `std::ops::Carrier` is not implemented for `()`
| in this macro invocation
|
= note: required by `std::ops::Carrier::from_error`
error: aborting due to previous error
```
This has been discussed at length in https://github.com/rust-lang/rust/issues/35946, but I figured it would be helpful to mention in the docs.
Reading user input is one of the first things beginners will look up in the docs, so my thinking was they'd see this warning here and not have to deal with the [tricky error message](https://blog.rust-lang.org/2017/03/02/lang-ergonomics.html).
If you think this isn't the right place to put this in the docs, that's understandable, I'm open to suggestions for putting it elsewhere or removing it entirely.
Add example to std::process::abort
This is a first step in order to complete this issue: https://github.com/rust-lang/rust/issues/29370
I submitted this PR with the help of @steveklabnik More info here: https://github.com/rust-lang/rust/issues/29370#issuecomment-290089330
It's my first PR on Rust, I'm learning how to contribute: Should I ping someone? I will post another PR with a more complicated example soon, I prefer send it separately (cause maybe I made some mistakes).
