RFC 248? I think you meant RFC 438.
There ain’t an RFC 248, while 438 looks to be what is being referred to:
https://github.com/rust-lang/rfcs/blob/master/text/0438-precedence-of-plus.md
--------------
Chis Morgan has a pretty important documentation fix in #19385 and he hasn't responded in a while to that pull request so I rebased it for him
Closes#19385
This commit completes the deprecation story for the in-tree serialization
library. The compiler will now emit a warning whenever it encounters
`deriving(Encodable)` or `deriving(Decodable)`, and the library itself is now
marked `#[unstable]` for when feature staging is enabled.
All users of serialization can migrate to the `rustc-serialize` crate on
crates.io which provides the exact same interface as the libserialize library
in-tree. The new deriving modes are named `RustcEncodable` and `RustcDecodable`
and require `extern crate "rustc-serialize" as rustc_serialize` at the crate
root in order to expand correctly.
To migrate all crates, add the following to your `Cargo.toml`:
[dependencies]
rustc-serialize = "0.1.1"
And then add the following to your crate root:
extern crate "rustc-serialize" as rustc_serialize;
Finally, rename `Encodable` and `Decodable` deriving modes to `RustcEncodable`
and `RustcDecodable`.
[breaking-change]
This commit completes the deprecation story for the in-tree serialization
library. The compiler will now emit a warning whenever it encounters
`deriving(Encodable)` or `deriving(Decodable)`, and the library itself is now
marked `#[unstable]` for when feature staging is enabled.
All users of serialization can migrate to the `rustc-serialize` crate on
crates.io which provides the exact same interface as the libserialize library
in-tree. The new deriving modes are named `RustcEncodable` and `RustcDecodable`
and require `extern crate "rustc-serialize" as rustc_serialize` at the crate
root in order to expand correctly.
To migrate all crates, add the following to your `Cargo.toml`:
[dependencies]
rustc-serialize = "0.1.1"
And then add the following to your crate root:
extern crate "rustc-serialize" as rustc_serialize;
Finally, rename `Encodable` and `Decodable` deriving modes to `RustcEncodable`
and `RustcDecodable`.
[breaking-change]
parse_ty() no longer takes a boolean parameter. quote_ty! implementation has not yet been modified accordingly.
As a matter of fact, quote_ty! was not covered by tests. One test (called qquotes) references it, but it has been ignored for nearly one year and now need heavy refactoring.
quote_token.rs seemed like a good place to test quote_ty!, many other quote_*! macros were asserted there.
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]
Normalize late-bound regions in bare functions, stack closures, and traits and include them in the generated hash.
Closes#19791
r? @nikomatsakis (does my normalization make sense?)
cc @alexcrichton
The primary focus of Rust's stability story at 1.0 is the standard library.
All other libraries distributed with the Rust compiler are planned to
be #[unstable] and therfore only accessible on the nightly channel of Rust. One
of the more widely used libraries today is libserialize, Rust's current solution
for encoding and decoding types.
The current libserialize library, however, has a number of drawbacks:
* The API is not ready to be stabilize as-is and we will likely not have enough
resources to stabilize the API for 1.0.
* The library is not necessarily the speediest implementations with alternatives
being developed out-of-tree (e.g. serde from erickt).
* It is not clear how the API of Encodable/Decodable can evolve over time while
maintaining backwards compatibility.
One of the major pros to the current libserialize, however, is
`deriving(Encodable, Decodable)` as short-hands for enabling serializing and
deserializing a type. This is unambiguously useful functionality, so we cannot
simply deprecate the in-tree libserialize in favor of an external crates.io
implementation.
For these reasons, this commit starts off a stability story for libserialize by
following these steps:
1. The deriving(Encodable, Decodable) modes will be deprecated in favor of a
renamed deriving(RustcEncodable, RustcDecodable).
2. The in-tree libserialize will be deprecated in favor of an external
rustc-serialize crate shipped on crates.io. The contents of the crate will be
the same for now (but they can evolve separately).
3. At 1.0 serialization will be performed through
deriving(RustcEncodable, RustcDecodable) and the rustc-serialize crate. The
expansions for each deriving mode will change from `::serialize::foo` to
`::rustc_serialize::foo`.
This story will require that the compiler freezes its implementation of
`RustcEncodable` deriving for all of time, but this should be a fairly minimal
maintenance burden. Otherwise the crate in crates.io must always maintain the
exact definition of its traits, but the implementation of json, for example, can
continue to evolve in the semver-sense.
The major goal for this stabilization effort is to pave the road for a new
official serialization crate which can replace the current one, solving many of
its downsides in the process. We are not assuming that this will exist for 1.0,
hence the above measures. Some possibilities for replacing libserialize include:
* If plugins have a stable API, then any crate can provide a custom `deriving`
mode (will require some compiler work). This means that any new serialization
crate can provide its own `deriving` with its own backing
implementation, entirely obsoleting the current libserialize and fully
replacing it.
* Erick is exploring the possibility of code generation via preprocessing Rust
source files in the near term until plugins are stable. This strategy would
provide the same ergonomic benefit that `deriving` does today in theory.
So, in summary, the current libserialize crate is being deprecated in favor of
the crates.io-based rustc-serialize crate where the `deriving` modes are
appropriately renamed. This opens up space for a later implementation of
serialization in a more official capacity while allowing alternative
implementations to be explored in the meantime.
Concretely speaking, this change adds support for the `RustcEncodable` and
`RustcDecodable` deriving modes. After a snapshot is made warnings will be
turned on for usage of `Encodable` and `Decodable` as well as deprecating the
in-tree libserialize crate to encurage users to use rustc-serialize instead.
per rfc 459
cc https://github.com/rust-lang/rust/issues/19390
One question is: should we start by warning, and only switch to hard error later? I think we discussed something like this in the meeting.
r? @alexcrichton
- 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
In preparation for [removing the `std::cmp::Ordering` reexport](https://github.com/rust-lang/rust/issues/19253), this needs to be done to prevent errors like:
```
note: in expansion of #[deriving]
note: expansion site
error: unresolved name `std::cmp::Equal`
#[deriving(Clone, PartialEq, PartialOrd, Eq, Ord, Show)]
^~~
```
