Implements RFC 1845, adding implementations of:
* `From<&[T]>` for `Rc<[T]>`
* `From<&str>` for `Rc<str>`
* `From<String>` for `Rc<str>`
* `From<Box<T: ?Sized>>` for `Rc<T>`
* `From<Vec<T>>` for `Rc<[T]>`
* and likewise for `Arc<_>`
Also removes now-obsolete internal methods `Rc::__from_array` and
`Rc::__from_str`, replacing their use with `Rc::from`.
Minor rewrite of char primitive unicode intro.
Opened primarily to address #36998.
Despite my love for emoji, the heart example is a little confusing because both heart characters start with the same code point and there can be stark rendering differences across browsers. I also spelled out what each of the code points is in the code block, which (hopefully) sheds light why one character is one code point while the other is two.
Very much open to suggestion and improvements. I'm pretty tired when I wrote this so I might wake up and realize that this is making things more confusing 😅
Redox paths are problematic. It would make sense to add a `Scheme`
variant to the `std::path::Component` enum; but that would presumably be
a breaking change due to exhaustive matching. Alternately it could use
the existing `Prefix` variant, like Windows, but none of the existing
types of prefix make sense, Redox only has one kind, and adding a new
variant to that enum has the same issue as `Component`.
When walking parents for lints we want to be sure to hit `let` statements which
can have attributes, so hook up these statements in the HIR map.
Closes#43910
Eat open paren when parsing list in libsyntax/parse/attr.rs
This PR adds a small refactoring:
```diff
pub fn parse_meta_item_kind(&mut self) -> PResult<'a, ast::MetaItemKind> {
Ok(if self.eat(&token::Eq) {
ast::MetaItemKind::NameValue(self.parse_unsuffixed_lit()?)
- } else if self.token == token::OpenDelim(token::Paren) {
+ } else if self.eat(&token::OpenDelim(token::Paren)) {
ast::MetaItemKind::List(self.parse_meta_seq()?)
} else {
- self.eat(&token::OpenDelim(token::Paren));
ast::MetaItemKind::Word
})
}
```
in `parse_meta_item_kind()`, the parser calls `self.eat(&token::OpenDelim(token::Paren));` before returning `ast::MetaItemKind::Word` just to add `(` to expected token. It seems more natural to eat the paren when parsing `ast::MetaItemKind::List`.
Refactoring: move net specific file descriptor methods
Move the implementations of net specific file descriptor methods from
io to net. This makes it easier to exclude net at all if it is not needed
for a target.
Implement CompilerDesugaringKind enum
This is the first step outlined in #35946. I think that the variants of `CompilerDesugaringKind` should be changed, I didn't know what the official names for `...` and `<-` are.
I'm not to sure how tests for the compiler work, but I would imagine that tests should be added such that
`Symbol::intern(s) == CompilerDesugaringKind::from(s).as_symbol()` for valid `s`.
