ExamplesResults
product('ABCD', repeat=2)AA AB AC AD BA BB BC BD CA CB CC CD DA DB DC DD
permutations('ABCD', 2)AB AC AD BA BC BD CA CB CD DA DB DC
combinations('ABCD', 2)AB AC AD BC BD CD
combinations_with_replacement('ABCD', 2)AA AB AC AD BB BC BD CC CD DD

(echo:: @ )