Our docs were very basic for the various versions of from_utf8, so
this commit beefs them up.
It also improves docs for the &str variant's error, Utf8Error.
After submitting #28031, I ran a [script](https://gist.github.com/durka/a5243440697c780f669b) on the rest of src/ and found some anomalies. In this PR are the fixes that I thought were obvious (but I might be wrong!). The others I've submitted in issue #28037.
* Rename `Utf16Items` to `Utf16Decoder`. "Items" is meaningless.
* Generalize it to any `u16` iterator, not just `[u16].iter()`
* Make it yield `Result` instead of a custom `Utf16Item` enum that was isomorphic to `Result`. This enable using the `FromIterator for Result` impl.
* Replace `Utf16Item::to_char_lossy` with a `Utf16Decoder::lossy` iterator adaptor.
This is a [breaking change], but only for users of the unstable `rustc_unicode` crate.
I’d like this functionality to be stabilized and re-exported in `std` eventually, as the "low-level equivalent" of `String::from_utf16` and `String::from_utf16_lossy` like #27784 is the low-level equivalent of #27714.
CC @aturon, @alexcrichton
Reserving lower_bound bytes was just silly. It’d be perfectly reasonable
to have empty strings in the iterator, which could cause superfluous
reallocation of the string, or to have more than one byte per string,
which could cause additional reallocation (in practice it’ll balance
out). The added complexity of this logic is simply pointless, adding
a little bloat with no demonstrable advantage and slight disadvantage.
* Rename `utf16_items` to `decode_utf16`. "Items" is meaningless.
* Move it to `rustc_unicode::char`, exposed in `std::char`.
* Generalize it to any `u16` iterable, not just `&[u16]`.
* Make it yield `Result` instead of a custom `Utf16Item` enum that was isomorphic to `Result`. This enable using the `FromIterator for Result` impl.
* Add a `REPLACEMENT_CHARACTER` constant.
* Document how `result.unwrap_or(REPLACEMENT_CHARACTER)` replaces `Utf16Item::to_char_lossy`.
Rename String::into_boxed_slice -> into_boxed_str
This is the name that was decided in rust-lang/rfcs#1152, and it's
better if we say “boxed str” for `Box<str>`.
The old name `String::into_boxed_slice` is deprecated.
This is the name that was decided in rust-lang/rfcs#1152, and it's
better if we say “boxed str” for `Box<str>`.
The old name `String::into_boxed_slice` is deprecated.
This commit removes all unstable and deprecated functions in the standard
library. A release was recently cut (1.3) which makes this a good time for some
spring cleaning of the deprecated functions.
The replacements are functions that usually use a single `mem::transmute` in
their body and restrict input and output via more concrete types than `T` and
`U`. Worth noting are the `transmute` functions for slices and the `from_utf8*`
family for mutable slices. Additionally, `mem::transmute` was often used for
casting raw pointers, when you can already cast raw pointers just fine with
`as`.
This commit is an implementation of [RFC 1184][rfc] which tweaks the behavior of
the `#![no_std]` attribute and adds a new `#![no_core]` attribute. The
`#![no_std]` attribute now injects `extern crate core` at the top of the crate
as well as the libcore prelude into all modules (in the same manner as the
standard library's prelude). The `#![no_core]` attribute disables both std and
core injection.
[rfc]: https://github.com/rust-lang/rfcs/pull/1184
These new snapshots contain the knowledge of how to build the new triples of
32-bit MSVC and 32-bit FreeBSD, both of which should soon start having
nightlies/auto builders!
This does not currently register bitrig/freebsd snapshots but I believe those
will be retroactively added in the near future.
... matching the existing Index impls.
There is no reason not to if String implement DerefMut.
The code removed in `src/librustc/middle/effect.rs` was added in #9750
to prevent things like `s[0] = 0x80` where `s: String`,
but I belive became unnecessary when the Index(Mut) traits were introduced.
With the latter is provided by the `From` conversion trait, the former is now completely redundant. Their code is identical. Let’s deprecate now and plan to remove in the next cycle. (It’s `#[unstable]`.)
r? @alexcrichton
CC @nagisa
I had to use `impl<'a, V: Copy> Extend<(usize, &'a V)> for VecMap<V>` instead of `impl<'a, V: Copy> Extend<(&'a usize, &'a V)> for VecMap<V>` as that's what is needed for doing
```rust
let mut a = VecMap::new();
let b = VecMap::new();
b.insert(1, "foo");
a.extend(&b)
```
I can squash the commits after review.
r? @Gankro
Prefer String::from over from_str; String::from_str is unstable while
String::from is stable. Promote the latter by using it in examples.
Simply migrating unstable function to the closest alternative.
I was profiling my code again and this time AsRef<str> for String
was eating up a considerable chunk of my runtime; adding the inline
annotation made the program run almost twice as fast!
While I was at it I also added the annotation to other implementations
of AsRef as well as AsMut.
collections: Implement String::drain(range) according to RFC 574
`.drain(range)` is unstable and under feature(collections_drain).
This adds a safe way to remove any range of a String as efficiently as
possible.
As noted in the code, this drain iterator has none of the memory safety
issues of the vector version.
RFC tracking issue is #23055
`.drain(range)` is unstable and under feature(collections_drain).
This adds a safe way to remove any range of a String as efficiently as
possible.
As noted in the code, this drain iterator has none of the memory safety
issues of the vector version.
RFC tracking issue is #23055
These implementations were intended to be unstable, but currently the stability
attributes cannot handle a stable trait with an unstable `impl` block. This
commit also audits the rest of the standard library for explicitly-`#[unstable]`
impl blocks. No others were removed but some annotations were changed to
`#[stable]` as they're defacto stable anyway.
One particularly interesting `impl` marked `#[stable]` as part of this commit
is the `Add<&[T]>` impl for `Vec<T>`, which uses `push_all` and implicitly
clones all elements of the vector provided.
Closes#24791
This is an implementation of [RFC 1030][rfc] which adds these traits to the
prelude and additionally removes all inherent `into_iter` methods on collections
in favor of the trait implementation (which is now accessible by default).
[rfc]: https://github.com/rust-lang/rfcs/pull/1030
This is technically a breaking change due to the prelude additions and removal
of inherent methods, but it is expected that essentially no code breaks in
practice.
[breaking-change]
Closes#24538
as accepted in [RFC 526](https://github.com/rust-lang/rfcs/blob/master/text/0526-fmt-text-writer.md).
Note that this brand new method is marked as **stable**. I judged this safe enough: it’s simple enough that it’s very unlikely to change. Still, I can mark it unstable instead if you prefer.
r? @alexcrichton
This commit removes all the old casting/generic traits from `std::num` that are
no longer in use by the standard library. This additionally removes the old
`strconv` module which has not seen much use in quite a long time. All generic
functionality has been supplanted with traits in the `num` crate and the
`strconv` module is supplanted with the [rust-strconv crate][rust-strconv].
[rust-strconv]: https://github.com/lifthrasiir/rust-strconv
This is a breaking change due to the removal of these deprecated crates, and the
alternative crates are listed above.
[breaking-change]
