The [associated RFC][rfc] for possibly splitting out `flush` has been closed and
as a result there are no more blockers for stabilizing this method, so this
commit marks the method as such.
[rfc]: https://github.com/rust-lang/rfcs/pull/950
Most of the changes are cleanup facilitated by straight-forward attribute handling.
This is a minor [breaking-change] for users of `quote_stmt!` (returns `Option<P<Stmt>>` now) and some of the public methods in `Parser` (a few `Vec<Attribute>` arguments/returns were removed).
r? @nikomatsakis
The [associated RFC][rfc] for possibly splitting out `flush` has been closed and
as a result there are no more blockers for stabilizing this method, so this
commit marks the method as such.
[rfc]: https://github.com/rust-lang/rfcs/pull/950
This commit deprecates the `count`, `range` and `range_step` functions
in `iter`, in favor of range notation. To recover all existing
functionality, a new `step_by` adapter is provided directly on `ops::Range`
and `ops::RangeFrom`.
[breaking-change]
r? @alexcrichton
This commit deprecates the `count`, `range` and `range_step` functions
in `iter`, in favor of range notation. To recover all existing
functionality, a new `step_by` adapter is provided directly on `ops::Range`
and `ops::RangeFrom`.
[breaking-change]
The new `std::io` module has had some time to bake now, and this commit
stabilizes its functionality. There are still portions of the module which
remain unstable, and below contains a summart of the actions taken.
This commit also deprecates the entire contents of the `old_io` module in a
blanket fashion. All APIs should now have a reasonable replacement in the
new I/O modules.
Stable APIs:
* `std::io` (the name)
* `std::io::prelude` (the name)
* `Read`
* `Read::read`
* `Read::{read_to_end, read_to_string}` after being modified to return a `usize`
for the number of bytes read.
* `ReadExt`
* `Write`
* `Write::write`
* `Write::{write_all, write_fmt}`
* `WriteExt`
* `BufRead`
* `BufRead::{fill_buf, consume}`
* `BufRead::{read_line, read_until}` after being modified to return a `usize`
for the number of bytes read.
* `BufReadExt`
* `BufReader`
* `BufReader::{new, with_capacity}`
* `BufReader::{get_ref, get_mut, into_inner}`
* `{Read,BufRead} for BufReader`
* `BufWriter`
* `BufWriter::{new, with_capacity}`
* `BufWriter::{get_ref, get_mut, into_inner}`
* `Write for BufWriter`
* `IntoInnerError`
* `IntoInnerError::{error, into_inner}`
* `{Error,Display} for IntoInnerError`
* `LineWriter`
* `LineWriter::{new, with_capacity}` - `with_capacity` was added
* `LineWriter::{get_ref, get_mut, into_inner}` - `get_mut` was added)
* `Write for LineWriter`
* `BufStream`
* `BufStream::{new, with_capacities}`
* `BufStream::{get_ref, get_mut, into_inner}`
* `{BufRead,Read,Write} for BufStream`
* `stdin`
* `Stdin`
* `Stdin::lock`
* `Stdin::read_line` - added method
* `StdinLock`
* `Read for Stdin`
* `{Read,BufRead} for StdinLock`
* `stdout`
* `Stdout`
* `Stdout::lock`
* `StdoutLock`
* `Write for Stdout`
* `Write for StdoutLock`
* `stderr`
* `Stderr`
* `Stderr::lock`
* `StderrLock`
* `Write for Stderr`
* `Write for StderrLock`
* `io::Result`
* `io::Error`
* `io::Error::last_os_error`
* `{Display, Error} for Error`
Unstable APIs:
(reasons can be found in the commit itself)
* `Write::flush`
* `Seek`
* `ErrorKind`
* `Error::new`
* `Error::from_os_error`
* `Error::kind`
Deprecated APIs
* `Error::description` - available via the `Error` trait
* `Error::detail` - available via the `Display` implementation
* `thread::Builder::{stdout, stderr}`
Changes in functionality:
* `old_io::stdio::set_stderr` is now a noop as the infrastructure for printing
backtraces has migrated to `std::io`.
[breaking-change]
When this attribute is applied to a function, its return value gets the
noalias attribute, which is how you tell LLVM that the function returns
a \"new\" pointer that doesn't alias anything accessible to the caller,
i.e. it acts like a memory allocator.
Plain malloc doesn't need this attribute because LLVM already knows
about malloc and adds the attribute itself.
When this attribute is applied to a function, its return value gets the
noalias attribute, which is how you tell LLVM that the function returns
a "new" pointer that doesn't alias anything accessible to the caller,
i.e. it acts like a memory allocator.
Plain malloc doesn't need this attribute because LLVM already knows
about malloc and adds the attribute itself.
This commit stabilizes essentially all of the new `std::path` API. The
API itself is changed in a couple of ways (which brings it in closer
alignment with the RFC):
* `.` components are now normalized away, unless they appear at the
start of a path. This in turn effects the semantics of e.g. asking for
the file name of `foo/` or `foo/.`, both of which yield `Some("foo")`
now. This semantics is what the original RFC specified, and is also
desirable given early experience rolling out the new API.
* The `parent` method is now `without_file` and succeeds if, and only
if, `file_name` is `Some(_)`. That means, in particular, that it fails
for a path like `foo/../`. This change affects `pop` as well.
In addition, the `old_path` module is now deprecated.
[breaking-change]
r? @alexcrichton
This commit stabilizes essentially all of the new `std::path` API. The
API itself is changed in a couple of ways (which brings it in closer
alignment with the RFC):
* `.` components are now normalized away, unless they appear at the
start of a path. This in turn effects the semantics of e.g. asking for
the file name of `foo/` or `foo/.`, both of which yield `Some("foo")`
now. This semantics is what the original RFC specified, and is also
desirable given early experience rolling out the new API.
* The `parent` function now succeeds if, and only if, the path has at
least one non-root/prefix component. This change affects `pop` as
well.
* The `Prefix` component now involves a separate `PrefixComponent`
struct, to better allow for keeping both parsed and unparsed prefix data.
In addition, the `old_path` module is now deprecated.
Closes#23264
[breaking-change]
The end result is that common fields (id, name, attributes, etc.) are stored in now-structures `ImplItem` and `TraitItem`.
The signature of a method is no longer duplicated between methods with a body (default/impl) and those without, they now share `MethodSig`.
This is also a [breaking-change] because of minor bugfixes and changes to syntax extensions:
* `pub fn` methods in a trait no longer parse - remove the `pub`, it has no meaning anymore
* `MacResult::make_methods` is now `make_impl_items` and the return type has changed accordingly
* `quote_method` is gone, because `P<ast::Method>` doesn't exist and it couldn't represent a full method anyways - could be replaced by `quote_impl_item`/`quote_trait_item` in the future, but I do hope we realize how silly that combinatorial macro expansion is and settle on a single `quote` macro + some type hints - or just no types at all (only token-trees)
r? @nikomatsakis This is necessary (hopefully also sufficient) for associated constants.
I've made some minor changes from the implementation attached to the RFC to try to minimize codegen. The methods now take `&Debug` trait objects rather than being parameterized and there are inlined stub methods that call to non-inlined methods to do the work.
r? @alexcrichton
cc @huonw for the `derive(Debug)` changes.
This may not be quite ready to go out, I fixed some docs but suspect I missed a bunch.
I also wound up fixing a bunch of redundant `[]` suffixes, but on closer inspection I don't believe that can land until after a snapshot.
This is a hack, but I don't think we can do much better as long as `derive` is running at the syntax expansion phase.
If the `custom_derive` feature gate is enabled, this works with user-defined traits and syntax extensions. Without the gate, you can't use e.g. `#[derive_Clone]` directly, so this does not change the stable language.
To make this effective, we now check gated attributes both before and after macro expansion. This uncovered a number of tests that were missing feature gates.
This PR also cleans up the deriving code somewhat, and forbids some previously-meaningless attribute syntax. For this reason it's technically a
[breaking-change]
r? @sfackler
This is a hack, but I don't think we can do much better as long as `derive` is
running at the syntax expansion phase.
If the custom_derive feature gate is enabled, this works with user-defined
traits and syntax extensions. Without the gate, you can't use e.g. #[derive_Clone]
directly, so this does not change the stable language.
This commit also cleans up the deriving code somewhat, and forbids some
previously-meaningless attribute syntax. For this reason it's technically a
[breaking-change]
Unstable items used in a macro expansion will now always trigger
stability warnings, *unless* the unstable items are directly inside a
macro marked with `#[allow_internal_unstable]`. IOW, the compiler warns
unless the span of the unstable item is a subspan of the definition of a
macro marked with that attribute.
E.g.
#[allow_internal_unstable]
macro_rules! foo {
($e: expr) => {{
$e;
unstable(); // no warning
only_called_by_foo!();
}}
}
macro_rules! only_called_by_foo {
() => { unstable() } // warning
}
foo!(unstable()) // warning
The unstable inside `foo` is fine, due to the attribute. But the
`unstable` inside `only_called_by_foo` is not, since that macro doesn't
have the attribute, and the `unstable` passed into `foo` is also not
fine since it isn't contained in the macro itself (that is, even though
it is only used directly in the macro).
In the process this makes the stability tracking much more precise,
e.g. previously `println!("{}", unstable())` got no warning, but now it
does. As such, this is a bug fix that may cause [breaking-change]s.
The attribute is definitely feature gated, since it explicitly allows
side-stepping the feature gating system.
---
This updates `thread_local!` macro to use the attribute, since it uses
unstable features internally (initialising a struct with unstable
fields).
This commit performs a stabilization pass over the `std::fs` module now that
it's had some time to bake. The change was largely just adding `#[stable]` tags,
but there are a few APIs that remain `#[unstable]`.
The following apis are now marked `#[stable]`:
* `std::fs` (the name)
* `File`
* `Metadata`
* `ReadDir`
* `DirEntry`
* `OpenOptions`
* `Permissions`
* `File::{open, create}`
* `File::{sync_all, sync_data}`
* `File::set_len`
* `File::metadata`
* Trait implementations for `File` and `&File`
* `OpenOptions::new`
* `OpenOptions::{read, write, append, truncate, create}`
* `OpenOptions::open` - this function was modified, however, to not attempt to
reject cross-platform openings of directories. This means that some platforms
will succeed in opening a directory and others will fail.
* `Metadata::{is_dir, is_file, len, permissions}`
* `Permissions::{readonly, set_readonly}`
* `Iterator for ReadDir`
* `DirEntry::path`
* `remove_file` - like with `OpenOptions::open`, the extra windows code to
remove a readonly file has been removed. This means that removing a readonly
file will succeed on some platforms but fail on others.
* `metadata`
* `rename`
* `copy`
* `hard_link`
* `soft_link`
* `read_link`
* `create_dir`
* `create_dir_all`
* `remove_dir`
* `remove_dir_all`
* `read_dir`
The following apis remain `#[unstable]`.
* `WalkDir` and `walk` - there are many methods by which a directory walk can be
constructed, and it's unclear whether the current semantics are the right
ones. For example symlinks are not handled super well currently. This is now
behind a new `fs_walk` feature.
* `File::path` - this is an extra abstraction which the standard library
provides on top of what the system offers and it's unclear whether we should
be doing so. This is now behind a new `file_path` feature.
* `Metadata::{accessed, modified}` - we do not currently have a good
abstraction for a moment in time which is what these APIs should likely be
returning, so these remain `#[unstable]` for now. These are now behind a new
`fs_time` feature
* `set_file_times` - like with `Metadata::accessed`, we do not currently have
the appropriate abstraction for the arguments here so this API remains
unstable behind the `fs_time` feature gate.
* `PathExt` - the precise set of methods on this trait may change over time and
some methods may be removed. This API remains unstable behind the `path_ext`
feature gate.
* `set_permissions` - we may wish to expose a more granular ability to set the
permissions on a file instead of just a blanket \"set all permissions\" method.
This function remains behind the `fs` feature.
The following apis are now `#[deprecated]`
* The `TempDir` type is now entirely deprecated and is [located on
crates.io][tempdir] as the `tempdir` crate with [its source][github] at
rust-lang/tempdir.
[tempdir]: https://crates.io/crates/tempdir
[github]: https://github.com/rust-lang/tempdir
The stability of some of these APIs has been questioned over the past few weeks
in using these APIs, and it is intentional that the majority of APIs here are
marked `#[stable]`. The `std::fs` module has a lot of room to grow and the
material is [being tracked in a RFC issue][rfc-issue].
[rfc-issue]: rust-lang/rfcs#939
Closes#22879
[breaking-change]
Unstable items used in a macro expansion will now always trigger
stability warnings, *unless* the unstable items are directly inside a
macro marked with `#[allow_internal_unstable]`. IOW, the compiler warns
unless the span of the unstable item is a subspan of the definition of a
macro marked with that attribute.
E.g.
#[allow_internal_unstable]
macro_rules! foo {
($e: expr) => {{
$e;
unstable(); // no warning
only_called_by_foo!();
}}
}
macro_rules! only_called_by_foo {
() => { unstable() } // warning
}
foo!(unstable()) // warning
The unstable inside `foo` is fine, due to the attribute. But the
`unstable` inside `only_called_by_foo` is not, since that macro doesn't
have the attribute, and the `unstable` passed into `foo` is also not
fine since it isn't contained in the macro itself (that is, even though
it is only used directly in the macro).
In the process this makes the stability tracking much more precise,
e.g. previously `println!(\"{}\", unstable())` got no warning, but now it
does. As such, this is a bug fix that may cause [breaking-change]s.
The attribute is definitely feature gated, since it explicitly allows
side-stepping the feature gating system.
---
This updates `thread_local!` macro to use the attribute, since it uses
unstable features internally (initialising a struct with unstable
fields).
This commit performs a stabilization pass over the `std::fs` module now that
it's had some time to bake. The change was largely just adding `#[stable]` tags,
but there are a few APIs that remain `#[unstable]`.
The following apis are now marked `#[stable]`:
* `std::fs` (the name)
* `File`
* `Metadata`
* `ReadDir`
* `DirEntry`
* `OpenOptions`
* `Permissions`
* `File::{open, create}`
* `File::{sync_all, sync_data}`
* `File::set_len`
* `File::metadata`
* Trait implementations for `File` and `&File`
* `OpenOptions::new`
* `OpenOptions::{read, write, append, truncate, create}`
* `OpenOptions::open` - this function was modified, however, to not attempt to
reject cross-platform openings of directories. This means that some platforms
will succeed in opening a directory and others will fail.
* `Metadata::{is_dir, is_file, len, permissions}`
* `Permissions::{readonly, set_readonly}`
* `Iterator for ReadDir`
* `DirEntry::path`
* `remove_file` - like with `OpenOptions::open`, the extra windows code to
remove a readonly file has been removed. This means that removing a readonly
file will succeed on some platforms but fail on others.
* `metadata`
* `rename`
* `copy`
* `hard_link`
* `soft_link`
* `read_link`
* `create_dir`
* `create_dir_all`
* `remove_dir`
* `remove_dir_all`
* `read_dir`
The following apis remain `#[unstable]`.
* `WalkDir` and `walk` - there are many methods by which a directory walk can be
constructed, and it's unclear whether the current semantics are the right
ones. For example symlinks are not handled super well currently. This is now
behind a new `fs_walk` feature.
* `File::path` - this is an extra abstraction which the standard library
provides on top of what the system offers and it's unclear whether we should
be doing so. This is now behind a new `file_path` feature.
* `Metadata::{accessed, modified}` - we do not currently have a good
abstraction for a moment in time which is what these APIs should likely be
returning, so these remain `#[unstable]` for now. These are now behind a new
`fs_time` feature
* `set_file_times` - like with `Metadata::accessed`, we do not currently have
the appropriate abstraction for the arguments here so this API remains
unstable behind the `fs_time` feature gate.
* `PathExt` - the precise set of methods on this trait may change over time and
some methods may be removed. This API remains unstable behind the `path_ext`
feature gate.
* `set_permissions` - we may wish to expose a more granular ability to set the
permissions on a file instead of just a blanket "set all permissions" method.
This function remains behind the `fs` feature.
The following apis are now `#[deprecated]`
* The `TempDir` type is now entirely deprecated and is [located on
crates.io][tempdir] as the `tempdir` crate with [its source][github] at
rust-lang/tempdir.
[tempdir]: https://crates.io/crates/tempdir
[github]: https://github.com/rust-lang/tempdir
The stability of some of these APIs has been questioned over the past few weeks
in using these APIs, and it is intentional that the majority of APIs here are
marked `#[stable]`. The `std::fs` module has a lot of room to grow and the
material is [being tracked in a RFC issue][rfc-issue].
[rfc-issue]: https://github.com/rust-lang/rfcs/issues/939
[breaking-change]
