Add ExactSizeIterator impls for Hash{Map, Set, Table} #20915
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This commit also changes the return types of all `size_hint()` impls in these files from (uint, Option<uint>) to (usize, Option<usize>).
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r? @pcwalton (rust_highfive has picked a reviewer for you, use r? to override) |
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r? @gankro |
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| #[stable] | ||
| impl<'a, K, V> ExactSizeIterator for Iter<'a, K, V> { | ||
| #[inline] fn len(&self) -> usize { self.inner.len() } |
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I'm not sure this is strictly necessary, but sure.
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I figured I'd avoid the unnecessary size_hint() unwrap by just calling straight down, but these can be removed if desired.
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This is the strictly more correct thing, although if T: ExactSize, then size_hint is probably trivially inlineable to discard the upper-bound creation. This is fine as is; we need a better story for impl forwarding anyway (but thanks for soldiering through all this in the interim!)
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No problem! And I'll be happy to bring this in line with impl forwarding conventions if and when we get them if this happens to run afoul of them.
Add ExactSizeIterator impls for Hash{Map, Set, Table}
Reviewed-by: Gankro
Since
ExactSizeIteratorwas decoupled fromDoubleEndedIterator, it's now more or less "free" to implement ExactSizeIterator for these iterators. Not sure if this is even something that we want, but it was quick and easy enough to do that I thought I'd open a PR for it and see.This commit also changes the return types of all
size_hint()impls in these files from(uint, Option<uint>)to(usize, Option<usize>)since I was already in there and it's a closely related change.