Book: Be very explicit of lifetimes being descriptive
... not prescriptive. Pointed out in https://users.rust-lang.org/t/what-if-i-get-lifetimes-wrong/7535/4, which was a revelation to me and made me think this should be more clear in the book. I'm not sure if I got this entirely right or if the wording is good, but I figured a PR is more helpful than a simple issue.
r? @steveklabnik
Small Note: There's also https://github.com/rust-lang/book, should I have sent the PR there? It doesn't coincide with the online book though, so I figured it's better of here.
Add method str::repeat(self, usize) -> String
It is relatively simple to repeat a string n times:
`(0..n).map(|_| s).collect::<String>()`. It becomes slightly more
complicated to do it “right” (sizing the allocation up front), which
warrants a method that does it for us.
This method is useful in writing testcases, or when generating text.
`format!()` can be used to repeat single characters, but not repeating
strings like this.
rustdoc: print non-self arguments of bare functions and struct methods on their own line
This change alters the formatting rustdoc uses when it creates function and struct method documentation. For bare functions, each argument is printed on its own line. For struct methods, non-self arguments are printed on their own line. In both cases, no line breaks are introduced if there are no arguments, and for struct methods, no line breaks are introduced if there is only a single self argument. This should aid readability of long function signatures and allow for greater comprehension of these functions.
I've run rustdoc with these changes on my crate egg-mode and its set of dependencies and put the result [on my server](https://shiva.icesoldier.me/doc-custom/egg_mode/). Of note, here are a few shortcut links that highlight the changes:
* [Bare function with a long signature](https://shiva.icesoldier.me/doc-custom/egg_mode/place/fn.reverse_geocode.html)
* [Struct methods, with single self argument and with self and non-self arguments](https://shiva.icesoldier.me/doc-custom/egg_mode/tweet/struct.Timeline.html#method.reset)
* [Bare functions with no arguments](https://shiva.icesoldier.me/doc-custom/rand/fn.thread_rng.html) and [struct methods with no arguments](https://shiva.icesoldier.me/doc-custom/hyper/client/struct.Client.html#method.new) are left unchanged.
This PR consists of two commits: one for bare functions and one for struct methods.
Turn compatibility lint `match_of_unit_variant_via_paren_dotdot` into a hard error
The lint was introduced 10 months ago and made deny-by-default 7 months ago.
In case someone is still using it, https://github.com/rust-lang/rust/pull/36868 contains a stable replacement.
r? @nikomatsakis
configure: Add options for separate musl roots
This allows using the `./configure` script to enable rustbuild to compile
multiple musl targets at once. We'll hopefully use this soon on our bots to
produce a bunch of targets.
Add two functions to check type of given address
The is_v4 function returns true if the given IP is v4. The is_v6
function returns true if the IP is v6.
It is relatively simple to repeat a string n times:
`(0..n).map(|_| s).collect::<String>()`. It becomes slightly more
complicated to do it “right” (sizing the allocation up front), which
warrants a method that does it for us.
This method is useful in writing testcases, or when generating text.
`format!()` can be used to repeat single characters, but not repeating
strings like this.
Add ThreadId for comparing threads
This adds the capability to store and compare threads with the current calling thread via a new struct, `std:🧵:ThreadId`. Addresses the need outlined in issue #21507.
This avoids the need to add any special checks to the existing thread structs and does not rely on the system to provide an identifier for a thread, since it seems that this approach is unreliable and undesirable. Instead, this simply uses a lazily-created, thread-local `usize` whose value is copied from a global atomic counter. The code should be simple enough that it should be as much reliable as the `#[thread_local]` attribute it uses (however much that is).
`ThreadId`s can be compared directly for equality and have copy semantics.
Also see these other attempts:
- rust-lang/rust#29457
- rust-lang/rust#29448
- rust-lang/rust#29447
And this in the RFC repo: rust-lang/rfcs#1435
Logically, it's a vector of pairs, so might as well represent it that
way.
The commit also changes `scan_stack` so that it is initialized with the
default size, instead of the excessive `55 * linewidth` size, which it
usually doesn't get even close to reaching.
`opaque::Decoder::read_str` is very hot within `rustc` due to its use in
the reading of crate metadata, and it currently returns a `String`. This
commit changes it to instead return a `Cow<str>`, which avoids a heap
allocation.
This change reduces the number of calls to `malloc` by almost 10% in
some benchmarks.
This is a [breaking-change] to libserialize.
