The code example in the trait documentation of ExactSizeIterator
has an incorrect implementation of the len method that does not return
the number of times the example iterator 'Counter' will iterate. This
may confuse readers of the docs as the example code will compile but
doesn't uphold the trait's contract.
This is easily fixed by modifying the implementation of len and changing
the assert statement to actually assert the correct behaviour. I also
slightly modified a code comment to better reflect what the method
returns.
Clarify Extend behaviour wrt existing keys
This seems to be consistent with all the Extend implementations I found, and isn't documented anywhere else afaik.
Add impls for `&Wrapping`. Also `Sum`, `Product` impls for both `Wrapping` and `&Wrapping`.
There are two changes here (split into two commits):
- Ops for references to `&Wrapping` (`Add`, `Sub`, `Mul` etc.) similar to the way they are implemented for primitives.
- Impls for `iter::{Sum,Product}` for `Wrapping`.
As far as I know `impl` stability attributes don't really matter so I didn't bother breaking up the macro for two different kinds of stability. Happy to change if it does matter.
Implement 1581 (FusedIterator)
* [ ] Implement on patterns. See https://github.com/rust-lang/rust/issues/27721#issuecomment-239638642.
* [ ] Handle OS Iterators. A bunch of iterators (`Args`, `Env`, etc.) in libstd wrap platform specific iterators. The current ones all appear to be well-behaved but can we assume that future ones will be?
* [ ] Does someone want to audit this? On first glance, all of the iterators on which I implemented `FusedIterator` appear to be well-behaved but there are a *lot* of them so a second pair of eyes would be nice.
* I haven't touched rustc internal iterators (or the internal rand) because rustc doesn't actually call `fuse()`.
* `FusedIterator` can't be implemented on `std::io::{Bytes, Chars}`.
Closes: #35602 (Tracking Issue)
Implements: rust-lang/rfcs#1581
Although the set of APIs being stabilized this release is relatively small, the
trains keep going! Listed below are the APIs in the standard library which have
either transitioned from unstable to stable or those from unstable to
deprecated.
Stable
* `BTreeMap::{append, split_off}`
* `BTreeSet::{append, split_off}`
* `Cell::get_mut`
* `RefCell::get_mut`
* `BinaryHeap::append`
* `{f32, f64}::{to_degrees, to_radians}` - libcore stabilizations mirroring past
libstd stabilizations
* `Iterator::sum`
* `Iterator::product`
Deprecated
* `{f32, f64}::next_after`
* `{f32, f64}::integer_decode`
* `{f32, f64}::ldexp`
* `{f32, f64}::frexp`
* `num::One`
* `num::Zero`
Added APIs (all unstable)
* `iter::Sum`
* `iter::Product`
* `iter::Step` - a few methods were added to accomodate deprecation of One/Zero
Removed APIs
* `From<Range<T>> for RangeInclusive<T>` - everything about `RangeInclusive` is
unstable
Closes#27739Closes#27752Closes#32526Closes#33444Closes#34152
cc #34529 (new tracking issue)
split iter.rs into a directory of (implementation private) modules.
+ mod Adaptor structs
- Private fields need to be available both for them and Iterator
+ iterator (Iterator trait)
+ traits (FromIterator, traits but Iterator itself)
+ range (range related)
+ sources (Repeat, Once, Empty)
