--------
- [You can now use the `cfg(target_vendor)` attribute.][57465] E.g.
`#[cfg(target_vendor="linux")] fn main() { println!("Hello Linux!"); }`
+- [Integer patterns such as in a match expression can now be exhaustive.][56362]
+ E.g. You can have match statement on a `u8` that covers `0..=255` and
+ you would no longer be required to have a `_ => unreachable!()` case.
- [You can now have multiple patterns in `if let` and `while let`
expressions.][57532] You can do this with the same syntax as a `match`
expression. E.g.
```rust
enum Creature {
- Crab(String),
- Person(String),
+ Crab(String),
+ Lobster(String),
+ Person(String),
}
fn main() {
- let state = Creature::Crab("Ferrous");
+ let state = Creature::Crab("Ferris");
- if let Creature::Crab(name) | Creature::Person(name) {
- println!("This creature's name is: {}", name);
- }
+ if let Creature::Crab(name) | Creature::Person(name) = state {
+ println!("This creature's name is: {}", name);
+ }
}
```
- [You can now have irrefutable `if let` and `while let` patterns.][57535] Using
this feature will by default produce a warning as this behaviour can be
unintuitive. E.g. `if let _ = 5 {}`
-- [You can now use `let` bindings and pattern destructurcting in
- constant functions.][57175]
+- [You can now use `let` bindings, assignments, expression statements,
+ and irrefutable pattern destructuring in const functions.][57175]
+- [You can now call unsafe const functions.][57067] E.g.
+ ```rust
+ const unsafe fn foo() -> i32 { 5 }
+ const fn bar() -> i32 {
+ unsafe { foo() }
+ }
+ ```
- [You can now specify multiple attributes in a `cfg_attr` attribute.][57332]
E.g. `#[cfg_attr(all(), must_use, optimize)]`
- [You can now specify a specific alignment with the `#[repr(packed)]`
attribute.][57049] E.g. `#[repr(packed(2))] struct Foo(i16, i32);` is a struct
with an alignment of 2 bytes and a size of 6 bytes.
-- [You can now call unsafe constant functions.][57067] E.g.
- ```rust
- unsafe const fn foo() -> i32 { 5 }
- const fn bar() -> i32 {
- unsafe { foo() }
- }
- ```
-- [You can now import an item from a module as a `_`.][56303] This allows you to
+- [You can now import an item from a module as an `_`.][56303] This allows you to
import a trait's impls, and not have the name in the namespace. E.g.
```rust
use std::io::Read as _;
pub trait Read {}
```
- [`extern` functions will now abort by default when panicking.][55982]
+ This was previously undefined behaviour.
Compiler
--------
- [The mininum required LLVM version has been bumped to 6.0.][56642]
- [Added support for the PowerPC64 architecture on FreeBSD.][57615]
- [The `x86_64-fortanix-unknown-sgx` target support has been upgraded to
- tier 2 support.][57130] Visit the [platform support] page for information on
- Rust's platform support.
+ tier 2 support.][57130] Visit the [platform support][platform-support] page for
+ information on Rust's platform support.
- [Added support for the `thumbv7neon-linux-androideabi` and
`thumbv7neon-unknown-linux-gnueabihf` targets.][56947]
- [Added support for the `x86_64-unknown-uefi` target.][56769]
Libraries
---------
-- [The functions `overflowing_{add, sub, mul, shl, shr}` are now constant
+- [The methods `overflowing_{add, sub, mul, shl, shr}` are now `const`
functions for all numeric types.][57566]
-- [The `get` method for all `NonZero` types is now constant.][57167]
-- [The functions `count_ones`, `count_zeros`, `leading_zeros`, `trailing_zeros`,
- `swap_bytes`, `from_be`, `from_le`, `to_be`, `to_le` are now constant for all
+- [The methods `rotate_left`, `rotate_right`, and `wrapping_{add, sub, mul, shl, shr}`
+ are now `const` functions for all numeric types.][57105]
+- [The methods `is_positive` and `is_negative` are now `const` functions for
+ all signed numeric types.][57105]
+- [The `get` method for all `NonZero` types is now `const`.][57167]
+- [The methods `count_ones`, `count_zeros`, `leading_zeros`, `trailing_zeros`,
+ `swap_bytes`, `from_be`, `from_le`, `to_be`, `to_le` are now `const` for all
numeric types.][57234]
-- [`Ipv4Addr::new` is now a constant function][57234]
+- [`Ipv4Addr::new` is now a `const` function][57234]
Stabilized APIs
---------------
- [`unix::FileExt::read_exact_at`]
-- [`unix::FileExt::write_exact_at`]
+- [`unix::FileExt::write_all_at`]
- [`Option::transpose`]
- [`Result::transpose`]
- [`convert::identity`]
- [`pin::Pin`]
+- [`marker::Unpin`]
+- [`marker::PhantomPinned`]
- [`Vec::resize_with`]
- [`VecDeque::resize_with`]
- [`Duration::as_millis`]
- [`Duration::as_micros`]
- [`Duration::as_nanos`]
+
Cargo
-----
- [Cargo should now rebuild a crate if a file was modified during the initial
build.][cargo/6484]
+Compatibility Notes
+-------------------
+- The methods `str::{trim_left, trim_right, trim_left_matches, trim_right_matches}`
+ are now deprecated in the standard library, and their usage will now produce a warning.
+ Please use the `str::{trim_start, trim_end, trim_start_matches, trim_end_matches}`
+ methods instead.
[57615]: https://github.com/rust-lang/rust/pull/57615/
[57465]: https://github.com/rust-lang/rust/pull/57465/
[56303]: https://github.com/rust-lang/rust/pull/56303/
[56351]: https://github.com/rust-lang/rust/pull/56351/
[55982]: https://github.com/rust-lang/rust/pull/55982/
+[56362]: https://github.com/rust-lang/rust/pull/56362
+[57105]: https://github.com/rust-lang/rust/pull/57105
[cargo/6484]: https://github.com/rust-lang/cargo/pull/6484/
-[`unix::FileExt::read_exact_at`]: https://doc.rust-lang.org/std/os/unix/fs/trait.FileExt.html#read_exact_at
-[`unix::FileExt::write_exact_at`]: https://doc.rust-lang.org/std/os/unix/fs/trait.FileExt.html#write_exact_at
-[`Option::transpose`]: https://doc.rust-lang.org/std/option/enum.Option.html#transpose
-[`Result::transpose`]: https://doc.rust-lang.org/std/result/enum.Result.html#transpose
+[`unix::FileExt::read_exact_at`]: https://doc.rust-lang.org/std/os/unix/fs/trait.FileExt.html#method.read_exact_at
+[`unix::FileExt::write_all_at`]: https://doc.rust-lang.org/std/os/unix/fs/trait.FileExt.html#method.write_all_at
+[`Option::transpose`]: https://doc.rust-lang.org/std/option/enum.Option.html#method.transpose
+[`Result::transpose`]: https://doc.rust-lang.org/std/result/enum.Result.html#method.transpose
[`convert::identity`]: https://doc.rust-lang.org/std/convert/fn.identity.html
[`pin::Pin`]: https://doc.rust-lang.org/std/pin/struct.Pin.html
-[`Vec::resize_with`]: https://doc.rust-lang.org/std/vec/struct.Vec.html#resize_with
-[`VecDeque::resize_with`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#resize_with
-[`Duration::as_millis`]: https://doc.rust-lang.org/std/time/struct.Duration.html#as_millis
-[`Duration::as_micros`]: https://doc.rust-lang.org/std/time/struct.Duration.html#as_micros
-[`Duration::as_nanos`]: https://doc.rust-lang.org/std/time/struct.Duration.html#as_millis
-
+[`marker::Unpin`]: https://doc.rust-lang.org/stable/std/marker/trait.Unpin.html
+[`marker::PhantomPinned`]: https://doc.rust-lang.org/nightly/std/marker/struct.PhantomPinned.html
+[`Vec::resize_with`]: https://doc.rust-lang.org/std/vec/struct.Vec.html#method.resize_with
+[`VecDeque::resize_with`]: https://doc.rust-lang.org/std/collections/struct.VecDeque.html#method.resize_with
+[`Duration::as_millis`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.as_millis
+[`Duration::as_micros`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.as_micros
+[`Duration::as_nanos`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.as_nanos
+[platform-support]: https://forge.rust-lang.org/platform-support.html
Version 1.32.0 (2019-01-17)
==========================
projects / rust.git / blobdiff