Hi Guys, I am wondering what is the most efficient or idiomatic way to drop a range of elements from the front of a VecDeque and keep the last N elements? I see that truncate() drops elements nice and cleanly from the back but what is the equivalent to doing this at the front? It looks like I cou…

I think drop(vecdeque.drain(..hi)) should be the most efficient and idiomatic: unlike split off, it wouldn’t do an allocation.

Best Way to Drop Range of Elements From Front of VecDeque

scottmcm August 26, 2019, 4:15pm 4

@matklad's answer is the right option for now, but consider opening a PR to add truncate_front and seeing what the libs team has to say. It seems to me like a plausible thing to have.

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Best Way to Drop Range of Elements From Front of VecDeque

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