I've got an idea about improving Iterator. Since it came into my head I started noticing more and more places, where I wished I could use this. I didn't find any trace of anybody proposed it yet, so I'm giving it a shot. What do you think? Summary Add Iterator::extend method, which takes a collecti…

It sounds like a good idea to me! You might even use this in places where collect() is used now, if you can predict the capacity better than size_hint() reports, or if you want to reuse an existing allocation. (Both of which are already possible with Extend though.) One place where this might fal…

Related: https://github.com/rust-lang/rust/issues/45840#issuecomment-343346317

It is better to create this in internals .

Since the subject/object roles of self and arg are switched here compared to Vec, I'd suggest a different name (e.g., extend_into).

Thank you, @scottmcm , I've added my 5 cents there :slight_smile: Thank you, @dylan.dpc , I've created post there as well: Pre-RFC: Iterator::extend_into - libs - Rust Internals

Pre-RFC: Iterator::extend

CodeSandwich January 26, 2018, 7:14pm 3

Good point about naming, it should be something new, like extend_into.

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Pre-RFC: Iterator::extend

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