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
This commit is a second pass stabilization for the `std::comm` module,
performing the following actions:
* The entire `std::comm` module was moved under `std::sync::mpsc`. This movement
reflects that channels are just yet another synchronization primitive, and
they don't necessarily deserve a special place outside of the other
concurrency primitives that the standard library offers.
* The `send` and `recv` methods have all been removed.
* The `send_opt` and `recv_opt` methods have been renamed to `send` and `recv`.
This means that all send/receive operations return a `Result` now indicating
whether the operation was successful or not.
* The error type of `send` is now a `SendError` to implement a custom error
message and allow for `unwrap()`. The error type contains an `into_inner`
method to extract the value.
* The error type of `recv` is now `RecvError` for the same reasons as `send`.
* The `TryRecvError` and `TrySendError` types have had public reexports removed
of their variants and the variant names have been tweaked with enum
namespacing rules.
* The `Messages` iterator is renamed to `Iter`
This functionality is now all `#[stable]`:
* `Sender`
* `SyncSender`
* `Receiver`
* `std::sync::mpsc`
* `channel`
* `sync_channel`
* `Iter`
* `Sender::send`
* `Sender::clone`
* `SyncSender::send`
* `SyncSender::try_send`
* `SyncSender::clone`
* `Receiver::recv`
* `Receiver::try_recv`
* `Receiver::iter`
* `SendError`
* `RecvError`
* `TrySendError::{mod, Full, Disconnected}`
* `TryRecvError::{mod, Empty, Disconnected}`
* `SendError::into_inner`
* `TrySendError::into_inner`
This is a breaking change due to the modification of where this module is
located, as well as the changing of the semantics of `send` and `recv`. Most
programs just need to rename imports of `std::comm` to `std::sync::mpsc` and
add calls to `unwrap` after a send or a receive operation.
[breaking-change]
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
The methods `from_bits` and `from_bits_truncate` were missing from the
list of generated methods. Didn't see a useful way to abbreviate, so
added with the same docstrings used in the macro definition.
- The following operator traits now take their arguments by value: `Add`, `Sub`, `Mul`, `Div`, `Rem`, `BitAnd`, `BitOr`, `BitXor`, `Shl`, `Shr`. This breaks all existing implementations of these traits.
- The binary operation `a OP b` now "desugars" to `OpTrait::op_method(a, b)` and consumes both arguments.
- `String` and `Vec` addition have been changed to reuse the LHS owned value, and to avoid internal cloning. Only the following asymmetric operations are available: `String + &str` and `Vec<T> + &[T]`, which are now a short-hand for the "append" operation.
[breaking-change]
---
This passes `make check` locally. I haven't touch the unary operators in this PR, but converting them to by value should be very similar to this PR. I can work on them after this gets the thumbs up.
@nikomatsakis r? the compiler changes
@aturon r? the library changes. I think the only controversial bit is the semantic change of the `Vec`/`String` `Add` implementation.
cc #19148
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]
In regards to:
https://github.com/rust-lang/rust/issues/19253#issuecomment-64836729
This commit:
* Changes the #deriving code so that it generates code that utilizes fewer
reexports (in particur Option::* and Result::*), which is necessary to
remove those reexports in the future
* Changes other areas of the codebase so that fewer reexports are utilized
compiletest: compact "linux" "macos" etc.as "unix".
liballoc: remove a superfluous "use".
libcollections: remove invocations of deprecated methods in favor of
their suggested replacements and use "_" for a loop counter.
libcoretest: remove invocations of deprecated methods; also add
"allow(deprecated)" for testing a deprecated method itself.
libglob: use "cfg_attr".
libgraphviz: add a test for one of data constructors.
libgreen: remove a superfluous "use".
libnum: "allow(type_overflow)" for type cast into u8 in a test code.
librustc: names of static variables should be in upper case.
libserialize: v[i] instead of get().
libstd/ascii: to_lowercase() instead of to_lower().
libstd/bitflags: modify AnotherSetOfFlags to use i8 as its backend.
It will serve better for testing various aspects of bitflags!.
libstd/collections: "allow(deprecated)" for testing a deprecated
method itself.
libstd/io: remove invocations of deprecated methods and superfluous "use".
Also add #[test] where it was missing.
libstd/num: introduce a helper function to effectively remove
invocations of a deprecated method.
libstd/path and rand: remove invocations of deprecated methods and
superfluous "use".
libstd/task and libsync/comm: "allow(deprecated)" for testing
a deprecated method itself.
libsync/deque: remove superfluous "unsafe".
libsync/mutex and once: names of static variables should be in upper case.
libterm: introduce a helper function to effectively remove
invocations of a deprecated method.
We still see a few warnings about using obsoleted native::task::spawn()
in the test modules for libsync. I'm not sure how I should replace them
with std::task::TaksBuilder and native::task::NativeTaskBuilder
(dependency to libstd?)
Signed-off-by: NODA, Kai <nodakai@gmail.com>
This commit repurposes most statics as constants in the standard library itself,
with the exception of TLS keys which precisely have their own memory location as
an implementation detail.
This commit also rewrites the bitflags syntax to use `const` instead of
`static`. All invocations will need to replace the word `static` with `const`
when declaring flags.
Due to the modification of the `bitflags!` syntax, this is a:
[breaking-change]
If you didn't have a trailing comma at the end of the variants, you could use
any type you wanted, but if you used a trailing comma the macro would
erroneously require the bits be a u32.
In order to prevent users from having to manually implement Hash and Ord for
bitflags types, this commit derives these traits automatically.
This breaks code that has manually implemented any of these traits for types
created by the bitflags! macro. Change this code by removing implementations
of these traits.
[breaking-change]
Earlier commits have established a baseline of `experimental` stability
for all crates under the facade (so their contents are considered
experimental within libstd). Since `experimental` is `allow` by
default, we should use the same baseline stability for libstd itself.
This commit adds `experimental` tags to all of the modules defined in
`std`, and `unstable` to `std` itself.
This completes the last stage of the renaming of the comparison hierarchy of
traits. This change renames TotalEq to Eq and TotalOrd to Ord.
In the future the new Eq/Ord will be filled out with their appropriate methods,
but for now this change is purely a renaming change.
[breaking-change]
This is part of the ongoing renaming of the equality traits. See #12517 for more
details. All code using Eq/Ord will temporarily need to move to Partial{Eq,Ord}
or the Total{Eq,Ord} traits. The Total traits will soon be renamed to {Eq,Ord}.
cc #12517
[breaking-change]
1. Wherever the `buf` field of a `Formatter` was used, the `Formatter` is used
instead.
2. The usage of `write_fmt` is minimized as much as possible, the `write!` macro
is preferred wherever possible.
3. Usage of `fmt::write` is minimized, favoring the `write!` macro instead.
Previously, the `from_bits` function in the `std::bitflags::bitflags`
macro was marked as unsafe, as it did not check that the bits being
converted actually corresponded to flags.
This patch changes the function to check against the full set of
possible flags and return an `Option` which is `None` if a non-flag bit
is set. It also adds a `from_bits_truncate` function which simply zeros
any bits not corresponding to a flag.
This addresses the concern raised in https://github.com/mozilla/rust/pull/13897
I feel that this is a very vital, missing piece of functionality. This adds on to #13072.
Only bits used in the definition of the bitflag are considered for the universe set. This is a bit safer than simply inverting all of the bits in the wrapped value.
```rust
bitflags!(flags Flags: u32 {
FlagA = 0x00000001,
FlagB = 0x00000010,
FlagC = 0x00000100,
FlagABC = FlagA.bits
| FlagB.bits
| FlagC.bits
})
...
// `Not` implements set complement
assert!(!(FlagB | FlagC) == FlagA);
// `all` and `is_all` are the inverses of `empty` and `is_empty`
assert!(Flags::all() - FlagA == !FlagA);
assert!(FlagABC.is_all());
```
The intent of `std::bitflags` is to allow building type-safe wrappers
around C-style flags APIs. But in addition to construction these flags
from the Rust side, we need a way to convert them from the C
side. This patch adds a `from_bits` function, which is unsafe since
the bits in question may not represent a valid combination of flags.
The `std::bitflags::bitflags!` macro did not provide support for
adding attributes to the generated structure or flags, due to
limitations in the parser for macros. This patch works around the
parser limitations by requiring a `flags` keyword in the overall
`bitflags!` invocation, and a `static` keyword for each flag:
bitflags!(
#[deriving(Hash)]
#[doc="Three flags"]
flags Flags: u32 {
#[doc="The first flag"]
static FlagA = 0x00000001,
static FlagB = 0x00000010,
static FlagC = 0x00000100
}
)
