sort

(sort sequence predicate)

Sorts sequence using predicate, a two-argument comparison function that returns non-nil when its first argument should precede its second. A list is sorted destructively: its cons cells are rearranged in place, so use the return value rather than the original variable. A string sorts as a sequence of its characters and returns a new string (the original string is not modified). The sort is not stable, so the relative order of elements considered equal by predicate is unspecified.