Rust 1.26.0

Language

--------

- [Closures now implement Copy and/or Clone if all captured variables

implement either or both traits.][49299]

- [The inclusive range syntax e.g. for x in 0..=10 is now stable.][47813]

- [The '_ lifetime is now stable. The underscore lifetime can be used anywhere a

lifetime can be elided.][49458]

- [impl Trait is now stable allowing you to have abstract types in returns

or in function parameters.][49255] E.g. fn foo() -> impl Iterator or

fn open(path: impl AsRef).

- [Pattern matching will now automatically apply dereferences.][49394]

- [128-bit integers in the form of u128 and i128 are now stable.][49101]

- [main can now return Result<(), E: Debug>][49162] in addition to ().

- [A lot of operations are now available in a const context.][46882] E.g. You

can now index into constant arrays, reference and dereference into constants,

and use tuple struct constructors.

- [Fixed entry slice patterns are now stable.][48516] E.g.

  let points = [1, 2, 3, 4];
match points {
[1, 2, 3, 4] => println!("All points were sequential."),
_ => println!("Not all points were sequential."),
}

Compiler

--------

- [LLD is now used as the default linker for wasm32-unknown-unknown.][48125]

- [Fixed exponential projection complexity on nested types.][48296]

This can provide up to a ~12% reduction in compile times for certain crates.

- [Added the --remap-path-prefix option to rustc.][48359] Allowing you

to remap path prefixes outputted by the compiler.

- [Added powerpc-unknown-netbsd target.][48281]

Libraries

---------

- [Implemented From for usize & From<{u8, i16}> for isize.][49305]

- [Added hexadecimal formatting for integers with fmt::Debug][48978]

e.g. assert!(format!("{:02x?}", b"Foo\0") == "[46, 6f, 6f, 00]")

- [Implemented Default, Hash for cmp::Reverse.][48628]

- [Optimized str::repeat being 8x faster in large cases.][48657]

- [ascii::escape_default is now available in libcore.][48735]

- [Trailing commas are now supported in std and core macros.][48056]

- [Implemented Copy, Clone for cmp::Reverse][47379]

- [Implemented Clone for char::{ToLowercase, ToUppercase}.][48629]

Stabilized APIs

---------------

- [*const T::add]

- [*const T::copy_to_nonoverlapping]

- [*const T::copy_to]

- [*const T::read_unaligned]

- [*const T::read_volatile]

- [*const T::read]

- [*const T::sub]

- [*const T::wrapping_add]

- [*const T::wrapping_sub]

- [*mut T::add]

- [*mut T::copy_to_nonoverlapping]

- [*mut T::copy_to]

- [*mut T::read_unaligned]

- [*mut T::read_volatile]

- [*mut T::read]

- [*mut T::replace]

- [*mut T::sub]

- [*mut T::swap]

- [*mut T::wrapping_add]

- [*mut T::wrapping_sub]

- [*mut T::write_bytes]

- [*mut T::write_unaligned]

- [*mut T::write_volatile]

- [*mut T::write]

- [Box::leak]

- [FromUtf8Error::as_bytes]

- [LocalKey::try_with]

- [Option::cloned]

- [btree_map::Entry::and_modify]

- [fs::read_to_string]

- [fs::read]

- [fs::write]

- [hash_map::Entry::and_modify]

- [iter::FusedIterator]

- [ops::RangeInclusive]

- [ops::RangeToInclusive]

- [process::id]

- [slice::rotate_left]

- [slice::rotate_right]

- [String::retain]

Cargo

-----

- [Cargo will now output path to custom commands when -v is

passed with --list][cargo/5041]

- [The Cargo binary version is now the same as the Rust version][cargo/5083]

Misc

----

- [The second edition of "The Rust Programming Language" book is now recommended

over the first.][48404]

Compatibility Notes

-------------------

- [aliasing a Fn trait as dyn no longer works.][48481] E.g. the following

syntax is now invalid.

  use std::ops::Fn as dyn;
fn g(_: Box) {}

- [The result of dereferences are no longer promoted to 'static.][47408]

e.g.

  fn main() {
const PAIR: &(i32, i32) = &(0, 1);
let _reversed_pair: &'static _ = &(PAIR.1, PAIR.0); // Doesn't work
}

- [Deprecate AsciiExt trait in favor of inherent methods.][49109]

- [".e0" will now no longer parse as 0.0 and will instead cause

an error.][48235]

- [Removed hoedown from rustdoc.][48274]

- [Bounds on higher-kinded lifetimes a hard error.][48326]

[46882]: https://github.com/rust-lang/rust/pull/46882

[47379]: https://github.com/rust-lang/rust/pull/47379

[47408]: https://github.com/rust-lang/rust/pull/47408

[47813]: https://github.com/rust-lang/rust/pull/47813

[48056]: https://github.com/rust-lang/rust/pull/48056

[48125]: https://github.com/rust-lang/rust/pull/48125

[48235]: https://github.com/rust-lang/rust/pull/48235

[48274]: https://github.com/rust-lang/rust/pull/48274

[48281]: https://github.com/rust-lang/rust/pull/48281

[48296]: https://github.com/rust-lang/rust/pull/48296

[48326]: https://github.com/rust-lang/rust/pull/48326

[48359]: https://github.com/rust-lang/rust/pull/48359

[48404]: https://github.com/rust-lang/rust/pull/48404

[48481]: https://github.com/rust-lang/rust/pull/48481

[48516]: https://github.com/rust-lang/rust/pull/48516

[48628]: https://github.com/rust-lang/rust/pull/48628

[48629]: https://github.com/rust-lang/rust/pull/48629

[48657]: https://github.com/rust-lang/rust/pull/48657

[48735]: https://github.com/rust-lang/rust/pull/48735

[48978]: https://github.com/rust-lang/rust/pull/48978

[49101]: https://github.com/rust-lang/rust/pull/49101

[49109]: https://github.com/rust-lang/rust/pull/49109

[49162]: https://github.com/rust-lang/rust/pull/49162

[49255]: https://github.com/rust-lang/rust/pull/49255

[49299]: https://github.com/rust-lang/rust/pull/49299

[49305]: https://github.com/rust-lang/rust/pull/49305

[49394]: https://github.com/rust-lang/rust/pull/49394

[49458]: https://github.com/rust-lang/rust/pull/49458

[*const T::add]: https://doc.rust-lang.org/std/primitive.pointer.html#method.add

[*const T::copy_to_nonoverlapping]: https://doc.rust-lang.org/std/primitive.pointer.html#method.copy_to_nonoverlapping

[*const T::copy_to]: https://doc.rust-lang.org/std/primitive.pointer.html#method.copy_to

[*const T::read_unaligned]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read_unaligned

[*const T::read_volatile]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read_volatile

[*const T::read]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read

[*const T::sub]: https://doc.rust-lang.org/std/primitive.pointer.html#method.sub

[*const T::wrapping_add]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_add

[*const T::wrapping_sub]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_sub

[*mut T::add]: https://doc.rust-lang.org/std/primitive.pointer.html#method.add-1

[*mut T::copy_to_nonoverlapping]: https://doc.rust-lang.org/std/primitive.pointer.html#method.copy_to_nonoverlapping-1

[*mut T::copy_to]: https://doc.rust-lang.org/std/primitive.pointer.html#method.copy_to-1

[*mut T::read_unaligned]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read_unaligned-1

[*mut T::read_volatile]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read_volatile-1

[*mut T::read]: https://doc.rust-lang.org/std/primitive.pointer.html#method.read-1

[*mut T::replace]: https://doc.rust-lang.org/std/primitive.pointer.html#method.replace

[*mut T::sub]: https://doc.rust-lang.org/std/primitive.pointer.html#method.sub-1

[*mut T::swap]: https://doc.rust-lang.org/std/primitive.pointer.html#method.swap

[*mut T::wrapping_add]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_add-1

[*mut T::wrapping_sub]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_sub-1

[*mut T::write_bytes]: https://doc.rust-lang.org/std/primitive.pointer.html#method.write_bytes

[*mut T::write_unaligned]: https://doc.rust-lang.org/std/primitive.pointer.html#method.write_unaligned

[*mut T::write_volatile]: https://doc.rust-lang.org/std/primitive.pointer.html#method.write_volatile

[*mut T::write]: https://doc.rust-lang.org/std/primitive.pointer.html#method.write

[Box::leak]: https://doc.rust-lang.org/std/boxed/struct.Box.html#method.leak

[FromUtf8Error::as_bytes]: https://doc.rust-lang.org/std/string/struct.FromUtf8Error.html#method.as_bytes

[LocalKey::try_with]: https://doc.rust-lang.org/std/thread/struct.LocalKey.html#method.try_with

[Option::cloned]: https://doc.rust-lang.org/std/option/enum.Option.html#method.cloned

[btree_map::Entry::and_modify]: https://doc.rust-lang.org/std/collections/btree_map/enum.Entry.html#method.and_modify

[fs::read_to_string]: https://doc.rust-lang.org/std/fs/fn.read_to_string.html

[fs::read]: https://doc.rust-lang.org/std/fs/fn.read.html

[fs::write]: https://doc.rust-lang.org/std/fs/fn.write.html

[hash_map::Entry::and_modify]: https://doc.rust-lang.org/std/collections/hash_map/enum.Entry.html#method.and_modify

[iter::FusedIterator]: https://doc.rust-lang.org/std/iter/trait.FusedIterator.html

[ops::RangeInclusive]: https://doc.rust-lang.org/std/ops/struct.RangeInclusive.html

[ops::RangeToInclusive]: https://doc.rust-lang.org/std/ops/struct.RangeToInclusive.html

[process::id]: https://doc.rust-lang.org/std/process/fn.id.html

[slice::rotate_left]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate_left

[slice::rotate_right]: https://doc.rust-lang.org/std/primitive.slice.html#method.rotate_right

[String::retain]: https://doc.rust-lang.org/std/string/struct.String.html#method.retain

[cargo/5041]: https://github.com/rust-lang/cargo/pull/5041

[cargo/5083]: https://github.com/rust-lang/cargo/pull/5083