and true X if true X if false Y add 0 X and false false add s s first 0 X nil first s cons cons from cons and 1 true 0 if 1 false 0 add 1 0 0 s 0 first 2 nil 0 cons 0 from 0 FULL ./TRS/TRCSR/Ex15_Luc98_L.trs