This commit introduces the syntax for negative implementations of traits
as shown below:
`impl !Trait for Type {}`
cc #13231
Part of RFC rust-lang/rfcs#127
r? @nikomatsakis
which should always result in an error.
NB. Some of the hunks in this commit rely on a later commit which adds
`tcx` into `param_env` and modifies `ParameterEnvironment` to
implement `Typer`.
This commit is an implementation of [RFC 503][rfc] which is a stabilization
story for the prelude. Most of the RFC was directly applied, removing reexports.
Some reexports are kept around, however:
* `range` remains until range syntax has landed to reduce churn.
* `Path` and `GenericPath` remain until path reform lands. This is done to
prevent many imports of `GenericPath` which will soon be removed.
* All `io` traits remain until I/O reform lands so imports can be rewritten all
at once to `std::io::prelude::*`.
This is a breaking change because many prelude reexports have been removed, and
the RFC can be consulted for the exact list of removed reexports, as well as to
find the locations of where to import them.
[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0503-prelude-stabilization.md
[breaking-change]
Closes#20068
Uses the same approach as https://github.com/rust-lang/rust/pull/17286 (and
subsequent changes making it more correct), where the visitor will skip any
pieces of the AST that are from "foreign code", where the spans don't line up,
indicating that that piece of code is due to a macro expansion.
If this breaks your code, read the error message to determine which feature
gate you should add to your crate.
Closes#18102
[breaking-change]
Uses the same approach as https://github.com/rust-lang/rust/pull/17286 (and
subsequent changes making it more correct), where the visitor will skip any
pieces of the AST that are from "foreign code", where the spans don't line up,
indicating that that piece of code is due to a macro expansion.
If this breaks your code, read the error message to determine which feature
gate you should add to your crate, and bask in the knowledge that your code
won't mysteriously break should you try to use the 1.0 release.
Closes#18102
[breaking-change]
This stabilizes most methods on `&str` working with patterns in a way that is forwards-compatible with a generic string pattern matching API:
- Methods that are using the primary name for their operation are marked as `#[stable]`, as they can be upgraded to a full `Pattern` API later without existing code breaking. Example: `contains(&str)`
- Methods that are using a more specific name in order to not clash with the primary one are marked as `#[unstable]`, as they will likely be removed once their functionality is merged into the primary one. Example: `contains_char<C: CharEq>(C)`
- The method docs got changed to consistently refer to the pattern types as a pattern.
- Methods whose names do not match in the context of the more generic API got renamed. Example: `trim_chars -> trim_matches`
Additionally, all methods returning iterators got changed to return unique new types with changed names in accordance with the new naming guidelines.
See also https://github.com/rust-lang/rfcs/pull/528
Due to some deprecations and type changes, this is a
[breaking-change]
followed by a semicolon.
This allows code like `vec![1i, 2, 3].len();` to work.
This breaks code that uses macros as statements without putting
semicolons after them, such as:
fn main() {
...
assert!(a == b)
assert!(c == d)
println(...);
}
It also breaks code that uses macros as items without semicolons:
local_data_key!(foo)
fn main() {
println("hello world")
}
Add semicolons to fix this code. Those two examples can be fixed as
follows:
fn main() {
...
assert!(a == b);
assert!(c == d);
println(...);
}
local_data_key!(foo);
fn main() {
println("hello world")
}
RFC #378.
Closes#18635.
[breaking-change]
This change makes the compiler no longer infer whether types (structures
and enumerations) implement the `Copy` trait (and thus are implicitly
copyable). Rather, you must implement `Copy` yourself via `impl Copy for
MyType {}`.
A new warning has been added, `missing_copy_implementations`, to warn
you if a non-generic public type has been added that could have
implemented `Copy` but didn't.
For convenience, you may *temporarily* opt out of this behavior by using
`#![feature(opt_out_copy)]`. Note though that this feature gate will never be
accepted and will be removed by the time that 1.0 is released, so you should
transition your code away from using it.
This breaks code like:
#[deriving(Show)]
struct Point2D {
x: int,
y: int,
}
fn main() {
let mypoint = Point2D {
x: 1,
y: 1,
};
let otherpoint = mypoint;
println!("{}{}", mypoint, otherpoint);
}
Change this code to:
#[deriving(Show)]
struct Point2D {
x: int,
y: int,
}
impl Copy for Point2D {}
fn main() {
let mypoint = Point2D {
x: 1,
y: 1,
};
let otherpoint = mypoint;
println!("{}{}", mypoint, otherpoint);
}
This is the backwards-incompatible part of #13231.
Part of RFC #3.
[breaking-change]
'Numeric' is the proper name of the unicode character class,
and this frees up the word 'digit' for ascii use in libcore.
Since I'm going to rename `Char::is_digit_radix` to
`is_digit`, I am not leaving a deprecated method in place,
because that would just cause name clashes, as both
`Char` and `UnicodeChar` are in the prelude.
[breaking-change]
This is especially useful for declaring a static with external linkage in an executable. There isn't any way to do that currently since we mark everything in an executable as internal by default.
Also, a quick fix to have the no-compiler-rt target option respected when building staticlibs as well.
This breaks code that referred to variant names in the same namespace as
their enum. Reexport the variants in the old location or alter code to
refer to the new locations:
```
pub enum Foo {
A,
B
}
fn main() {
let a = A;
}
```
=>
```
pub use self::Foo::{A, B};
pub enum Foo {
A,
B
}
fn main() {
let a = A;
}
```
or
```
pub enum Foo {
A,
B
}
fn main() {
let a = Foo::A;
}
```
[breaking-change]
