Rewrite of a paragraph in in the `match` section.
The colon `:` should be used only when the sentence preceeding it is a
complete sentence. If this is not the case, then a `;` should be used;
this denotes that the following fragment is a part of the previous
fragment.
I got a new bike; it has two wheels. (Similar to I got a new bike, it has two wheels)
The ice cream truck has great flavours; blueberry, blackberry, berryberry.
Writing a complete sentence:
- with a list under it
- You can join two sentences with it: Much like this.
r? @steveklabnik
Some history:
While getting Rust to 1.0, it was a struggle to keep the book in a
working state. I had always wanted a certain kind of TOC, but couldn't
quite get it there.
At the 11th hour, I wrote up "Rust inside other langauges" and "Dining
Philosophers" in an attempt to get the book in the direction I wanted to
go. They were fine, but not my best work. I wanted to further expand
this section, but it's just never going to end up happening. We're doing
the second draft of the book now, and these sections are basically gone
already.
Here's the issues with these two sections, and removing them just fixes
it all:
// Philosophers
There was always controversy over which ones were chosen, and why. This
is kind of a perpetual bikeshed, but it comes up every once in a while.
The implementation was originally supposed to show off channels, but
never did, due to time constraints. Months later, I still haven't
re-written it to use them.
People get different results and assume that means they're wrong, rather
than the non-determinism inherent in concurrency. Platform differences
aggrivate this, as does the exact amount of sleeping and printing.
// Rust Inside Other Languages
This section is wonderful, and shows off a strength of Rust. However,
it's not clear what qualifies a language to be in this section. And I'm
not sure how tracking a ton of other languages is gonna work, into the
future; we can't test _anything_ in this section, so it's prone to
bitrot.
By removing this section, and making the Guessing Game an initial
tutorial, we will move this version of the book closer to the future
version, and just eliminate all of these questions.
In addition, this also solves the 'split-brained'-ness of having two
paths, which has endlessly confused people in the past.
I'm sad to see these sections go, but I think it's for the best.
Fixes#30471Fixes#30163Fixes#30162Fixes#25488Fixes#30345Fixes#28713Fixes#28915
And probably others. This lengthy list alone is enough to show that
these should have been removed.
RIP.
Didn't build/test the change, but if that one-character fix isn't correct, I'll eat my hat. :-) Found this reading the book over the last week or two since Mozlando -- much enjoying the book so far.
book: Some operator fixes for the syntax index
- Correct the names of the comparison traits (PartialOrd)
- Mention only the traits that overload the operator (PartialOrd,
PartialEq), not operator-unrelated traits (Ord, Eq).
- Add `!=` operator.
- Correct the names of the comparison traits (PartialOrd)
- Mention only the traits that overload the operator (PartialOrd,
PartialEq), not operator-unrelated traits (Ord, Eq).
- Add `!=` operator.
The website will [shortly](https://github.com/rust-lang/rust-www/pull/241) provide the main documentation landing page as well as the [FAQ](https://github.com/rust-lang/rust-www/issues/202). All of the content here will be there.
This strips out everything and makes the index *just* an index into the in-tree content. My only real qualm with this is that this will become the content on doc.rust-lang.org (a sweet URL), while the main documentation page will be www.rust-lang.org/documentation.html.
r? @steveklabnik
correcting use of ':' in sentences.
The colon `:` should be used only when the sentence preceeding it is a
complete sentence. If this is not the case, then a `;` should be used;
this denotes that the following fragment is a part of the previous
fragment.
This PR is a rebase of the original PR by @eddyb https://github.com/rust-lang/rust/pull/21836 with some unrebasable parts manually reapplied, feature gate added + type equality restriction added as described below.
This implementation is partial because the type equality restriction is applied to all type ascription expressions and not only those in lvalue contexts. Thus, all difficulties with detection of these contexts and translation of coercions having effect in runtime are avoided.
So, you can't write things with coercions like `let slice = &[1, 2, 3]: &[u8];`. It obviously makes type ascription less useful than it should be, but it's still much more useful than not having type ascription at all.
In particular, things like `let v = something.iter().collect(): Vec<_>;` and `let u = t.into(): U;` work as expected and I'm pretty happy with these improvements alone.
Part of https://github.com/rust-lang/rust/issues/23416
The previous example had no chance of compiling in either form, due to the restrictive follow set for `ty`. This one has the desired behavior: http://is.gd/kYdw4g (well, I don't exactly desire this behavior at all, but it's true at least :p )
The Rustonomicon's Lifetimes chapter uses the idiom "big ask", which is obscure compared to "tall order" (check [Google ngrams](https://books.google.com/ngrams/graph?content=big+ask%2C+tall+order&year_start=1800)). Also, it's easily mistaken for a typo; either "a big task" or "a big thing to ask" could plausibly work there.
r? @steveklabnik
…entation clearer
I could not use colors as suggested for #29854 because Github doesn't support these in markdown, however this solution may be better for color-blind readers.
The Rustonomicon's Lifetimes chapter uses the idiom "big ask", which is obscure compared to "tall order" (check Google ngrams). Also, it's easily mistaken for a typo; either "a big task" or "a big thing to ask" could plausibly work there.
Closes https://github.com/rust-lang/rust/issues/29935
The attributes `deprecated` and `rustc_deprecated` are completely independent in this implementation and it leads to some noticeable code duplication. Representing `deprecated` as
```
Stability {
level: Stable { since: "" },
feature: "",
depr: Some(Deprecation),
}
```
or, contrariwise, splitting rustc_deprecation from stability makes most of the duplication go away.
I can do this refactoring, but before doing it I must be sure, that further divergence of `deprecated` and `rustc_deprecated` is certainly not a goal.
cc @llogiq
The previous example had no chance of compiling in either form, due to the restrictive follow set for `ty`. This one has the desired behavior: http://is.gd/kYdw4g (well, I don't exactly desire this behavior at all, but it's true at least :p )
r? @steveklabnik
Currently neither the API docs nor the book clearly explain that out-of-bounds array indexing causes a panic. Since this is fairly important and seems to surprise a number of new Rust programmers, I think it's worth adding to both places. (But if you think it would be better to put this info in the API docs only, that's fine too.)
Some specific things I'd like feedback on:
* The new text here talks about panicking, which hasn't been formally introduced at this point in chapter 5 (though it has been mentioned in previous sections too).
* Similarly the `Vec::get` example uses `Option<T>` which hasn't been fully introduced yet. Should we leave out this example?
The example code in the Channels subsection of the rust book give warnings about
unused result which must be used, #[warn(unused_must_use)] on by default
Added a small pattern match to resolve those warnings.
This commit is the standard API stabilization commit for the 1.6 release cycle.
The list of issues and APIs below have all been through their cycle-long FCP and
the libs team decisions are listed below
Stabilized APIs
* `Read::read_exact`
* `ErrorKind::UnexpectedEof` (renamed from `UnexpectedEOF`)
* libcore -- this was a bit of a nuanced stabilization, the crate itself is now
marked as `#[stable]` and the methods appearing via traits for primitives like
`char` and `str` are now also marked as stable. Note that the extension traits
themeselves are marked as unstable as they're imported via the prelude. The
`try!` macro was also moved from the standard library into libcore to have the
same interface. Otherwise the functions all have copied stability from the
standard library now.
* `fs::DirBuilder`
* `fs::DirBuilder::new`
* `fs::DirBuilder::recursive`
* `fs::DirBuilder::create`
* `os::unix::fs::DirBuilderExt`
* `os::unix::fs::DirBuilderExt::mode`
* `vec::Drain`
* `vec::Vec::drain`
* `string::Drain`
* `string::String::drain`
* `vec_deque::Drain`
* `vec_deque::VecDeque::drain`
* `collections::hash_map::Drain`
* `collections::hash_map::HashMap::drain`
* `collections::hash_set::Drain`
* `collections::hash_set::HashSet::drain`
* `collections::binary_heap::Drain`
* `collections::binary_heap::BinaryHeap::drain`
* `Vec::extend_from_slice` (renamed from `push_all`)
* `Mutex::get_mut`
* `Mutex::into_inner`
* `RwLock::get_mut`
* `RwLock::into_inner`
* `Iterator::min_by_key` (renamed from `min_by`)
* `Iterator::max_by_key` (renamed from `max_by`)
Deprecated APIs
* `ErrorKind::UnexpectedEOF` (renamed to `UnexpectedEof`)
* `OsString::from_bytes`
* `OsStr::to_cstring`
* `OsStr::to_bytes`
* `fs::walk_dir` and `fs::WalkDir`
* `path::Components::peek`
* `slice::bytes::MutableByteVector`
* `slice::bytes::copy_memory`
* `Vec::push_all` (renamed to `extend_from_slice`)
* `Duration::span`
* `IpAddr`
* `SocketAddr::ip`
* `Read::tee`
* `io::Tee`
* `Write::broadcast`
* `io::Broadcast`
* `Iterator::min_by` (renamed to `min_by_key`)
* `Iterator::max_by` (renamed to `max_by_key`)
* `net::lookup_addr`
New APIs (still unstable)
* `<[T]>::sort_by_key` (added to mirror `min_by_key`)
Closes#27585Closes#27704Closes#27707Closes#27710Closes#27711Closes#27727Closes#27740Closes#27744Closes#27799Closes#27801
cc #27801 (doesn't close as `Chars` is still unstable)
Closes#28968
This commit is the standard API stabilization commit for the 1.6 release cycle.
The list of issues and APIs below have all been through their cycle-long FCP and
the libs team decisions are listed below
Stabilized APIs
* `Read::read_exact`
* `ErrorKind::UnexpectedEof` (renamed from `UnexpectedEOF`)
* libcore -- this was a bit of a nuanced stabilization, the crate itself is now
marked as `#[stable]` and the methods appearing via traits for primitives like
`char` and `str` are now also marked as stable. Note that the extension traits
themeselves are marked as unstable as they're imported via the prelude. The
`try!` macro was also moved from the standard library into libcore to have the
same interface. Otherwise the functions all have copied stability from the
standard library now.
* The `#![no_std]` attribute
* `fs::DirBuilder`
* `fs::DirBuilder::new`
* `fs::DirBuilder::recursive`
* `fs::DirBuilder::create`
* `os::unix::fs::DirBuilderExt`
* `os::unix::fs::DirBuilderExt::mode`
* `vec::Drain`
* `vec::Vec::drain`
* `string::Drain`
* `string::String::drain`
* `vec_deque::Drain`
* `vec_deque::VecDeque::drain`
* `collections::hash_map::Drain`
* `collections::hash_map::HashMap::drain`
* `collections::hash_set::Drain`
* `collections::hash_set::HashSet::drain`
* `collections::binary_heap::Drain`
* `collections::binary_heap::BinaryHeap::drain`
* `Vec::extend_from_slice` (renamed from `push_all`)
* `Mutex::get_mut`
* `Mutex::into_inner`
* `RwLock::get_mut`
* `RwLock::into_inner`
* `Iterator::min_by_key` (renamed from `min_by`)
* `Iterator::max_by_key` (renamed from `max_by`)
Deprecated APIs
* `ErrorKind::UnexpectedEOF` (renamed to `UnexpectedEof`)
* `OsString::from_bytes`
* `OsStr::to_cstring`
* `OsStr::to_bytes`
* `fs::walk_dir` and `fs::WalkDir`
* `path::Components::peek`
* `slice::bytes::MutableByteVector`
* `slice::bytes::copy_memory`
* `Vec::push_all` (renamed to `extend_from_slice`)
* `Duration::span`
* `IpAddr`
* `SocketAddr::ip`
* `Read::tee`
* `io::Tee`
* `Write::broadcast`
* `io::Broadcast`
* `Iterator::min_by` (renamed to `min_by_key`)
* `Iterator::max_by` (renamed to `max_by_key`)
* `net::lookup_addr`
New APIs (still unstable)
* `<[T]>::sort_by_key` (added to mirror `min_by_key`)
Closes#27585Closes#27704Closes#27707Closes#27710Closes#27711Closes#27727Closes#27740Closes#27744Closes#27799Closes#27801
cc #27801 (doesn't close as `Chars` is still unstable)
Closes#28968
See https://github.com/rust-lang/rfcs/pull/16 and https://github.com/rust-lang/rust/issues/15701
- Added syntax support for attributes on expressions and all syntax nodes in statement position.
- Extended `#[cfg]` folder to allow removal of statements, and
of expressions in optional positions like expression lists and trailing
block expressions.
- Extended lint checker to recognize lint levels on expressions and
locals.
- As per RFC, attributes are not yet accepted on `if` expressions.
Examples:
```rust
let x = y;
{
...
}
assert_eq!((1, #[cfg(unset)] 2, 3), (1, 3));
let FOO = 0;
```
Implementation wise, there are a few rough corners and open questions:
- The parser work ended up a bit ugly.
- The pretty printer change was based mostly on guessing.
- Similar to the `if` case, there are some places in the grammar where a new `Expr` node starts,
but where it seemed weird to accept attributes and hence the parser doesn't. This includes:
- const expressions in patterns
- in the middle of an postfix operator chain (that is, after `.`, before indexing, before calls)
- on range expressions, since `#[attr] x .. y` parses as `(#[attr] x) .. y`, which is inconsistent with
`#[attr] .. y` which would parse as `#[attr] (.. y)`
- Attributes are added as additional `Option<Box<Vec<Attribute>>>` fields in expressions and locals.
- Memory impact has not been measured yet.
- A cfg-away trailing expression in a block does not currently promote the previous `StmtExpr` in a block to a new trailing expr. That is to say, this won't work:
```rust
let x = {
#[cfg(foo)]
Foo { data: x }
#[cfg(not(foo))]
Foo { data: y }
};
```
- One-element tuples can have their inner expression removed to become Unit, but just Parenthesis can't. Eg, `(#[cfg(unset)] x,) == ()` but `(#[cfg(unset)] x) == error`. This seemed reasonable to me since tuples and unit are type constructors, but could probably be argued either way.
- Attributes on macro nodes are currently unconditionally dropped during macro expansion, which seemed fine since macro disappear at that point?
- Attributes on `ast::ExprParens` will be prepend-ed to the inner expression in the hir folder.
- The work on pretty printer tests for this did trigger, but not fix errors regarding macros:
- expression `foo![]` prints as `foo!()`
- expression `foo!{}` prints as `foo!()`
- statement `foo![];` prints as `foo!();`
- statement `foo!{};` prints as `foo!();`
- statement `foo!{}` triggers a `None` unwrap ICE.
Replace the old link pointing to an out-of-date gist with a
link to the lazy_static crate on crates.io.
We also don't need to state the author, as the crates.io page
shows the authors and owners.
I think this fixes#30137. I basically just repeated some details that were scattered around other places in this document, and emphasized that you probably don't want an `extern crate` or `mod` statement to end up inside a function.
The documentation shows this:
[dependencies]
rand="0.3.0"
and says it allows any version compatible with 0.3.0, but then it says, "If we wanted to use only 0.3.0 exactly, we could use `=0.3.0`." That is very easy to misunderstand, so hopefully this PR will help others not to be as confused as me. :-)
I think this fixes#30137. I basically just repeated some details that were scattered around other places in this document, and emphasized that you probably don't want an `extern crate` or `mod` statement to end up inside a function.
* `const`: Add reference to raw pointers
* Change `expr!(...)` etc. examples to use `ident` instead.
*Technically*, it should be `pat`, but that's not how it works in
practice.
* `|`: add reference to closure syntax.
* Closure syntax entry.
* Indexing and slicing entries.
The `f` argument will reference the actual value in the `d` box, not the box in the `bar`'s stack frame.
I am just learning Rust, so I don't know how to explain this well, but just from `f`'s type it is clear that it will be a pointer to an `i32`, not a pointer to a pointer. Some `println!("{:p}", ...)`'s can easily confirm this.
I would actually suggest to remove/simplify this part of the example. This is a subtle issue that can easily confuse people at the early stages of familiarizing with the language. (As I got confused by it. :))