Isn't Positions == FilterMapSpecialCase<Enumerate<Iter>, FilterMapSpecialCasePositions>?

rust-itertools / itertools

Extra iterator adaptors, iterator methods, free functions, and macros.

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Isn't Positions == FilterMapSpecialCase<Enumerate<Iter>, FilterMapSpecialCasePositions>? #892

Open phimuemue opened 4 months ago

phimuemue commented 4 months ago

We have FilterMapOk and we have Positions.

I think we should make type FilterMapOk<Iter> = FilterMapSpecialCase<Iter, FilterMapSpecialCaseFnOk> and type Positions = FilterMapSpecialCase<Enumerate<Iter>, FilterMapSpecialCasePositions>.

Would enforce consitency for DoubleEndedIterator, fusedness, etc.

Philippe-Cholet commented 4 months ago

Wow... that's bold, intriguing and definitely interesting. I'm curious how it would impact benchmarks (for Positions mainly, since FilterMapOk might end up deprecated with #844).