MutableSequence

A Sequence whose contents can be modified in place. MutableSequence is the receiver for the mutating methods of Sequence (append, insert, remove, etc.). IoSeq_insertSeqEvery(aSequence, aNumberOfItems)

Inserts aSequence every aNumberOfItems. Returns self.

IoSeq_leaveThenRemove(aNumberToLeave, aNumberToRemove)

Leaves aNumberToLeave items then removes aNumberToRemove items. Returns self.