mutable.Buffer.remove(index, count) is inconsistent with mutable.Buffer.remove(index)

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The mutable.BufferLike has this nice remove method which returns the removed item as well as mutating the mutable collection:

def remove(index: Int): A

But, it also has this remove method which takes in a count but does NOT return back the removed items:

def remove(index: Int, count: Int): Unit

The above method should not return an Unit but the list of removed items.

See: https://github.com/scala/scala/blob/5562e1a2eb07b9a541b3eac85a809847e2d48763/src/library/scala/collection/mutable/BufferLike.scala#L106-L121

All we need to do is to change the lines for (i <- 0 until count) remove(n) to (0 until count).map(i => remove(n))

This change should be backwards compatible since it was earlier returning an Unit anyway.

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Imported From: https://issues.scala-lang.org/browse/SI-9882?orig=1 Reporter: Pathikrit Bhowmick (pathikritbhowmick-at-msn.com)

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@SethTisue said: Note that the workaround is to call slice first, before remove.

I guess if we made this change, the result type ought to match slice's result type, so your proposed code change would need some refinement.

It's not a no-brainer that this change is desirable; single-element remove never needs to allocate, but multi-element remove would have to allocate. If the return value is usually ignored, then allocating is undesirable.