When self.start > self.end, these iterators simply return None,
so we adjust the size_hint to just return zero in this case.
Certain optimizations can be implemented in and outside libstd if we
know we can trust the size_hint for all inputs to for example
Range<usize>.
This corrects the ExactSizeIterator implementations, which IMO were
unsound and incorrect previously, since they allowed a range like (2..1)
to return a size_hint of -1us in when debug assertions are turned off.
Given `<expr> as Box<Trait>`, infer that `Box<_>` is expected type for `<expr>`.
This is useful for addressing fallout from newly proposed box protocol; see #22006 for examples of such fallout, much of which will be unnecessary with this fix.
When trying to build against a newer, local LLVM version it might be
preferable to have a flag to disable the LLVM version check instead of
having to modify the configure script.
Fixes#21998
Simplify cache selection by just using the local cache whenever there
are any where-clauses at all. This seems to be the simplest possible
rule and will (hopefully!) put an end to these annoying "cache leak"
bugs. Fixes#22019.
r? @aturon
```rust
#[plugin] #[no_link] extern crate bleh;
```
becomes a crate attribute
```rust
#![plugin(bleh)]
```
The feature gate is still required.
It's almost never correct to link a plugin into the resulting library / executable, because it will bring all of libsyntax and librustc with it. However if you really want this behavior, you can get it with a separate `extern crate` item in addition to the `plugin` attribute.
Fixes#21043.
Fixes#20769.
[breaking-change]
This commit is an implementation of [RFC 739][rfc] which adds a new `std::fs`
module to the standard library. This module provides much of the same
functionality as `std::old_io::fs` but it has many tweaked APIs as well as uses
the new `std::path` module.
[rfc]: https://github.com/rust-lang/rfcs/pull/739
This commit is an implementation of [RFC 739][rfc] which adds a new `std::fs`
module to the standard library. This module provides much of the same
functionality as `std::old_io::fs` but it has many tweaked APIs as well as uses
the new `std::path` module.
[rfc]: https://github.com/rust-lang/rfcs/pull/739
Right now it is not possible to write a `for` loop without opting-in to the
`core` feature due to the way they're expanding (calling
`::std::iter::IntoIterator::into_iter`). There are some planned tweaks to the
`IntoIterator` trait (adding an `Item` associated type) which will cause
implementations of `IntoIterator` to break, but the *usage* of the trait is
currently stable.
This commit marks the method `into_iter` as stable as the name will not be
changing, nor the fact that it takes no arguments and returns one type (which is
determiend by the `Self` type). This means that usage of `for` loops is now
stable but manual implementations of the `IntoIterator` trait will continue to
be unstable.
This is in preparation for stabilization of the `IntoIterator` trait. All
implementations and references to `Iter` need to be renamed to `IntoIter`.
[breaking-change]
#[plugin] #[no_link] extern crate bleh;
becomes a crate attribute
#![plugin(bleh)]
The feature gate is still required.
It's almost never correct to link a plugin into the resulting library /
executable, because it will bring all of libsyntax and librustc with it.
However if you really want this behavior, you can get it with a separate
`extern crate` item in addition to the `plugin` attribute.
Fixes#21043.
Fixes#20769.
[breaking-change]
This allows people to write tools which are drop-in replacements for rustc by implementing `CompilerCalls` and three lines of code, rather than having to copy+paste a bunch of args parsing code.
r? @alexcrichton
