- Various grammatical changes
- Place punctuation outside of key term quotes
- Change comment placement in 17.2 code block
- Replace double hyphens with en dashes
Rewrite how the HRTB algorithm matches impls against obligations. Instead of impls providing higher-ranked trait-references, impls now once again only have early-bound regions. The skolemization checks are thus moved out into trait matching itself. This allows to implement "perfect forwarding" impls like those described in #19730. This PR builds on a previous PR that was already reviewed by @pnkfelix.
r? @pnkfelix
Fixes#19730
This fixes#19978. The bug was introduced by 570325d, where if the type
of an Fn has not been inferred (strs[0] is "_") we slice from 1 to
0. We now explicitly check if `strs[0]` is a single element tuple.
lifetimes. This currently causes an ICE; it should (ideally) work, but
failing that at least give a structured error. For the purposes of
this PR, though, workaround is fine.
read (`//!` is intrusive) and annoying to edit (must maintain a prefix
on every line). Since the only purpose of a `doc.rs` file is to have a
bunch of text, using `/*!` and `*/` without indentations seems
appropriate.
This PR substantially narrows the notion of a "runtime" in Rust, and allows calling into Rust code directly without any setup or teardown.
After this PR, the basic "runtime support" in Rust will consist of:
* Unwinding and backtrace support
* Stack guards
Other support, such as helper threads for timers or the notion of a "current thread" are initialized automatically upon first use.
When using Rust in an embedded context, it should now be possible to call a Rust function directly as a C function with absolutely no setup, though in that case panics will cause the process to abort. In this regard, the C/Rust interface will look much like the C/C++ interface.
In more detail, this PR:
* Merges `librustrt` back into `std::rt`, undoing the facade. While doing so, it removes a substantial amount of redundant functionality (such as mutexes defined in the `rt` module). Code using `librustrt` can now call into `std::rt` to e.g. start executing Rust code with unwinding support.
* Allows all runtime data to be initialized lazily, including the "current thread", the "at_exit" infrastructure, and the "args" storage.
* Deprecates and largely removes `std::task` along with the widespread requirement that there be a "current task" for many APIs in `std`. The entire task infrastructure is replaced with `std::thread`, which provides a more standard API for manipulating and creating native OS threads. In particular, it's possible to join on a created thread, and to get a handle to the currently-running thread. In addition, threads are equipped with some basic blocking support in the form of `park`/`unpark` operations (following a tradition in some OSes as well as the JVM). See the `std::thread` documentation for more details.
* Channels are refactored to use a new internal blocking infrastructure that itself sits on top of `park`/`unpark`.
One important change here is that a Rust program ends when its main thread does, following most threading models. On the other hand, threads will often be created with an RAII-style join handle that will re-institute blocking semantics naturally (and with finer control).
This is very much a:
[breaking-change]
Closes#18000
r? @alexcrichton
The [final step](https://github.com/rust-lang/rust/pull/19654) of
runtime removal changes the threading/process model so that the process
shuts down when the main thread exits. But several shared resources,
like the helper thread for timeouts, are shut down when the main thread
exits (but before the process ends), and they are not prepared to be
used after shut down, but other threads may try to access them during
the shutdown sequence of the main thread.
As an interim solution, the `at_exit` cleanup routine is simply skipped.
Ultimately, these resources should be made to safely handle asynchronous
shutdown, usually by panicking if called from a detached thread when the
main thread is ending.
See issue for details https://github.com/rust-lang/rust/issues/20012
This is a [breaking-change] for anyone relying on `at_exit`.
This flag is somewhat tied to the `unwind` module rather than the `thread_info`
module, so this commit moves it into that module as well as allowing the same OS
thread to call `unwind::try` multiple times. Previously once a thread panicked
its panic flag was never reset, even after exiting the panic handler.
The current implementations use `std::sync` primitives, but these primitives
currently end up relying on `thread_info` and a local `Thread` being available
(mainly for checking the panicking flag).
To get around this, this commit lowers the abstractions used by the windows
thread_local implementation as well as the at_exit_imp module. Both of these
modules now use a `sys::Mutex` and a `static mut` and manage the
allocation/locking manually.
This commit is part of a series that introduces a `std::thread` API to
replace `std::task`.
In the new API, `spawn` returns a `JoinGuard`, which by default will
join the spawned thread when dropped. It can also be used to join
explicitly at any time, returning the thread's result. Alternatively,
the spawned thread can be explicitly detached (so no join takes place).
As part of this change, Rust processes now terminate when the main
thread exits, even if other detached threads are still running, moving
Rust closer to standard threading models. This new behavior may break code
that was relying on the previously implicit join-all.
In addition to the above, the new thread API also offers some built-in
support for building blocking abstractions in user space; see the module
doc for details.
Closes#18000
[breaking-change]
We need to be sure to init thread_info before we init args for example because
args is grabbing locks which may entail looking at the local thread eventually.
This commit removes the runtime bookkeeping previously used to ensure
that all Rust tasks were joined before the runtime was shut down.
This functionality will be replaced by an RAII style `Thread` API, that
will also offer a detached mode.
Since this changes the semantics of shutdown, it is a:
[breaking-change]
This commit merges the `rustrt` crate into `std`, undoing part of the
facade. This merger continues the paring down of the runtime system.
Code relying on the public API of `rustrt` will break; some of this API
is now available through `std::rt`, but is likely to change and/or be
removed very soon.
[breaking-change]
- The following operator traits now take their argument by value: `Neg`, `Not`. This breaks all existing implementations of these traits.
- The unary operation `OP a` now "desugars" to `OpTrait::op_method(a)` and consumes its argument.
[breaking-change]
---
r? @nikomatsakis This PR is very similar to the binops-by-value PR
cc @aturon
It is useful to move all the elements out of some collections without
deallocating the underlying buffer. It came up in IRC, and this patch
implements it as `drain`. This has been discussed as part of RFC 509.
r? @Gankro
cc: @frankmcsherry
This commit modifies rustdoc to not require these empty modules to be public in
the standard library. The modules still remain as a location to attach
documentation to, but the modules themselves are now private (don't have to
commit to an API). The documentation for the standard library now shows all of
the primitive types on the main index page.
The current indentation level would indicate that Boolean literals are on the same level as Integer and Float literals under Number literals, unindenting moves it to the same scope as Character and string literals, Byte and byte string literals, and Number literals under Literals.
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]
---
Rebased version of #18958
r? @alexcrichton
cc @pcwalton
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]
Windows dbghelp strips leading underscores from symbols, and I could not find a way to turn this off. So let's accept "ZN...E" form too.
Also, print PC displacement from symbols. This is helpful in gauging whether the PC was indeed within the function displayed in the backtrace, or whether it just happened to be the closest public symbol in the module.
There is currently no way to specify the stability level for a trait
impl produced by `deriving`. This patch is a stopgap solution that:
* Turns of stability inheritance for trait impls, and
* Uses the stability level of the *trait* if no level is directly
specified.
That is, manual trait impls may still provide a directly stability
level, but `deriving` will use the level of the trait. While not a
perfect solution, it should be good enough for 1.0 API stabilization, as
we will like *remove* any unwanted impls outright.
This narrows the definition of nested returns such that only when the
outer return has a chance of being executed (due to the inner return
being conditional) do we mark the function as having nested returns.
Fixes#19684
This is to encourage the use of the sugary syntax instead of the `<>` syntax, which will not be usable post-1.0. Rustdoc [still uses the `<>` syntax](https://github.com/rust-lang/rust/issues/19909), so if a rustdoc wizard is looking for something to do, it would be nice to use the parenthetical syntax there as well. (I tried to patch rustdoc as well, but failed…)
Fixes some tuple indexing deprecation warnings. Didn't test. Don't see how it could fail unless I need to modify a makefile somewhere...
r? @alexcrichton
Was testing rustup on a very minimal Debian installation and got errors during the install process (error occurred in `install.sh` of the Rust nightly.)
Noticed that Rustup was downloading the i686 nightly instead of x86-64. Installing `file` fixed the problem, and this patch adds the probe to ensure file is installed before attempting to use it.
There may still be an issue with the i686 installation, I did not investigate further.
Added -Z print-region-graph debugging option; produces graphviz visualization of region inference constraint graph.
Optionally uses environment variables `RUST_REGION_GRAPH=<path_template>` and `RUST_REGION_GRAPH_NODE=<node-id>` to select which file to output to and which AST node to print.
Relax some of the bounds on the decoder methods back to FnMut to help accomodate
some more flavorful variants of decoders which may need to run the closure more
than once when it, for example, attempts to find the first successful enum to
decode.
In US english, "that" is used in restrictive clauses in place of
"which", and often affects the meaning of sentences.
In UK english and many dialects, no distinction is
made.
While Rust devs want to avoid unproductive pedanticism, it is worth at
least being uniform in documentation such as:
http://doc.rust-lang.org/std/iter/index.html
and also in cases where correct usage of US english clarifies the
sentence.
Includes a fix for a small mistake in `fn insert` which is caught by test_insert for len=15, but not len=7.
Part of #18424
r? @Gankro @csherratt @huonw
This test would read with a timeout and then send a UDP message, expecting the
message to be received. The receiving port, however, was bound in the child
thread so it could be the case that the timeout and send happens before the
child thread runs. To remedy this we just bind the port before the child thread
runs, moving it into the child later on.
cc #19120
- Change long inline code to code block
- Replace double-hyphens with en dash
- Miscellaneous rephrasings for clarity
**Edit**: Trivial `commit --amend` to change the commit message slightly.
This commit takes a second pass through the `std::option` module to fully
stabilize any lingering methods inside of it.
These items were made stable as-is
* Some
* None
* as_mut
* expect
* unwrap
* unwrap_or
* unwrap_or_else
* map
* map_or
* map_or_else
* and_then
* or_else
* unwrap_or_default
* Default implementation
* FromIterator implementation
* Copy implementation
These items were made stable with modifications
* iter - now returns a struct called Iter
* iter_mut - now returns a struct called IterMut
* into_iter - now returns a struct called IntoIter, Clone is never implemented
This is a breaking change due to the modifications to the names of the iterator
types returned. Code referencing the old names should updated to referencing the
newer names instead. This is also a breaking change due to the fact that
`IntoIter` no longer implements the `Clone` trait.
These items were explicitly not stabilized
* as_slice - waiting on indexing conventions
* as_mut_slice - waiting on conventions with as_slice as well
* cloned - the API was still just recently added
* ok_or - API remains experimental
* ok_or_else - API remains experimental
[breaking-change]
closes#12677 (cc @Valloric)
cc #15294
r? @aturon / @alexcrichton
(Because of #19358 I had to move the struct bounds from the `where` clause into the parameter list)
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
This commit deprecates a few more in-tree libs for their crates.io counterparts.
Note that this commit does not make use of the #[deprecated] tag to prevent
warnings from being generated for in-tree usage. Once #[unstable] warnings are
turned on then all external users will be warned to move.
These crates have all been duplicated in rust-lang/$crate repositories so
development can happen independently of the in-tree copies. We can explore at a
later date replacing the in-tree copies with the external copies, but at this
time the libraries have changed very little over the past few months so it's
unlikely for changes to be sent to both repos.
cc #19260
Hello! This is my first Rust patch, and I fear that I've probably skipped at least 7 critical steps. I'd appreciate your feedback and advice about how to contribute to Rust.
This patch is based on a discussion with @BurntSushi in #14602 a while back. I'm happy to revise it as needed to fit into the modern world. :-)
As discussed in that issue, the existing `at` and `name` functions represent two different results with the empty string:
1. Matched the empty string.
2. Did not match anything.
Consider the following example. This regex has two named matched groups, `key` and `value`. `value` is optional:
```rust
// Matches "foo", "foo;v=bar" and "foo;v=".
regex!(r"(?P<key>[a-z]+)(;v=(?P<value>[a-z]*))?");
```
We can access `value` using `caps.name("value")`, but there's no way for us to distinguish between the `"foo"` and `"foo;v="` cases.
Early this year, @BurntSushi recommended modifying the existing `at` and `name` functions to return `Option`, instead of adding new functions to the API.
This is a [breaking-change], but the fix is easy:
- `refs.at(1)` becomes `refs.at(1).unwrap_or("")`.
- `refs.name(name)` becomes `refs.name(name).unwrap_or("")`.
Using a type alias for iterator implementations is fragile since this exposes the implementation to users of the iterator, and any changes could break existing code.
This PR changes the iterators of `BTreeMap`, `BTreeSet`, `HashMap`, and `HashSet` to use proper new types, rather than type aliases. However, since it is fair-game to treat a type-alias as the aliased type, this is a:
[breaking-change].
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.
Using a type alias for iterator implementations is fragile since this
exposes the implementation to users of the iterator, and any changes
could break existing code.
This commit changes the iterators of `VecMap` to use
proper new types, rather than type aliases. However, since it is
fair-game to treat a type-alias as the aliased type, this is a:
[breaking-change].
Part of #18469
[breaking-change]
A receiver will only ever get a single auto-reference. Previously arrays and strings would get two, e.g., [T] would be auto-ref'ed to &&[T]. This is usually apparent when a trait is implemented for `&[T]` and has a method takes self by reference. The usual solution is to implement the trait for `[T]` (the DST form).
r? @nikomatsakis (or anyone else, really)
The names expected and actual are not used anymore in the output. It also
removes the confusion that the argument order is the opposite of junit.
Bug #7330 is relevant.
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
Was testing rustup on a very minimal Debian installation and got errors during the install process (error occurred in `install.sh` of the Rust nightly.)
Noticed that Rustup was downloading the i686 nightly instead of x86-64. Installing `file` fixed the problem, and this patch adds the probe to ensure file is installed before attempting to use it.
There may still be an issue with the i686 installation, I did not investigate further.
Part of #18469
[breaking-change]
A receiver will only ever get a single auto-reference. Previously arrays and strings would get two, e.g., [T] would be auto-ref'ed to &&[T]. This is usually apparent when a trait is implemented for `&[T]` and has a method takes self by reference. The usual solution is to implement the trait for `[T]` (the DST form).
This commit performs a second pass stabilization of the `std::default` module.
The module was already marked `#[stable]`, and the inheritance of `#[stable]`
was removed since this attribute was applied. This commit adds the `#[stable]`
attribute to the trait definition and one method name, along with all
implementations found in the standard distribution.
This commit takes a second pass through the `std::mem` module for stabilization.
The only remaining non-stable items in this module were `forget`, `transmute`,
`copy_lifetime`, and `copy_lifetime_mut`.
The `forget` and `transmute` intrinsics themselves were marked `#[stable]` to
propgate into the `core::mem` module so they would be marked stable.
The `copy_lifetime` functions were left `unstable`, but `Sized?` annotations
were added to the parameters to allow more general use with DSTs.
The `size_of_val`, `min_align_of_val`, and `align_of_val` functions would like
to grow `Sized?` bounds, but this is a backwards compatible change that
currently ICEs the compiler, so this change was not made at this time.
Finally, the module itself was declared `#![stable]` in this pass.
This commit collapses the various prelude traits for slices into just one trait:
* SlicePrelude/SliceAllocPrelude => SliceExt
* CloneSlicePrelude/CloneSliceAllocPrelude => CloneSliceExt
* OrdSlicePrelude/OrdSliceAllocPrelude => OrdSliceExt
* PartialEqSlicePrelude => PartialEqSliceExt
Using a type alias for iterator implementations is fragile since this
exposes the implementation to users of the iterator, and any changes
could break existing code.
This commit changes the iterators of `HashSet` to use
proper new types, rather than type aliases. However, since it is
fair-game to treat a type-alias as the aliased type, this is a:
[breaking-change].
Using a type alias for iterator implementations is fragile since this
exposes the implementation to users of the iterator, and any changes
could break existing code.
This commit changes the keys and values iterators of `HashMap` to use
proper new types, rather than type aliases. However, since it is
fair-game to treat a type-alias as the aliased type, this is a:
[breaking-change].
Using a type alias for iterator implementations is fragile since this
exposes the implementation to users of the iterator, and any changes
could break existing code.
This commit changes the iterators of `BTreeSet` to use
proper new types, rather than type aliases. However, since it is
fair-game to treat a type-alias as the aliased type, this is a:
[breaking-change].
Using a type alias for iterator implementations is fragile since this
exposes the implementation to users of the iterator, and any changes
could break existing code.
This commit changes the keys and values iterators of `BTreeMap` to use
proper new types, rather than type aliases. However, since it is
fair-game to treat a type-alias as the aliased type, this is a:
[breaking-change].
- 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
visualization of region inference constraint graph.
Optionally uses environment variables `RUST_REGION_GRAPH=<path_template>`
and `RUST_REGION_GRAPH_NODE=<node-id>` to select which file to output
to and which AST node to print.
Note that in some cases of method AST's, the identification of AST
node is based on the id for the *body* of the method; this is largely
due to having the body node-id already available at the relevant point
in the control-flow of rustc in its current incarnation. Ideally we
would handle identifying AST's by name in addition to node-id,
e.g. the same way that the pretty-printer supports path suffixes as
well as node-ids for identifying subtrees to print.
Relax some of the bounds on the decoder methods back to FnMut to help accomodate
some more flavorful variants of decoders which may need to run the closure more
than once when it, for example, attempts to find the first successful enum to
decode.
This a breaking change due to the bounds for the trait switching, and clients
will need to update from `FnOnce` to `FnMut` as well as likely making the local
function binding mutable in order to call the function.
[breaking-change]
This is not technically a [breaking-change], but it will be soon, so
you should update your code. Typically, shadowing is accidental, and
the shadowing lifetime can simply be removed. This frequently occurs
in constructor patterns:
```rust
// Old:
impl<'a> SomeStruct<'a> { fn new<'a>(..) -> SomeStruct<'a> { ... } }
// Should be:
impl<'a> SomeStruct<'a> { fn new(..) -> SomeStruct<'a> { ... } }
```
Otherwise, you should rename the inner lifetime to something
else. Note though that lifetime elision frequently applies:
```rust
// Old
impl<'a> SomeStruct<'a> {
fn get<'a>(x: &'a self) -> &'a T { &self.field }
}
// Should be:
impl<'a> SomeStruct<'a> {
fn get(x: &self) -> &T { &self.field }
}
``
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)]
^~~
```
On AArch64, libc::c_char is u8. There are some places in the code where i8 is assumed, which causes compilation errors.
(AArch64 is not officially supported yet, but this change does not hurt any other targets and makes the code future-proof.)
Build `clean::ConstantItem` values in the `inline` module and
pretty-print the AST for inlined const items.
Doc strings are still missing from inlined constants (see #19773).
Partially address #18156, #19722, #19185Fix#15821
r? @alexcrichton
This is a revival of #19517 (per request of @alexcrichton) now that the new snapshots have landed. We can now remove the last feature gates for if_let, while_let, and tuple_indexing scattered throughout the test sources since these features have been added to Rust.
Closes#19473.
