let s be SCM+FSA-State; :: thesis: for s1 being SCM-State holds s +* s1 is SCM+FSA-State
let s1 be SCM-State; :: thesis: s +* s1 is SCM+FSA-State
A1: dom (SCM*-VAL * SCM+FSA-OK) = SCM+FSA-Memory by Lm8;
then reconsider f = SCM*-VAL * SCM+FSA-OK as non-empty ManySortedSet of SCM+FSA-Memory by PARTFUN1:def 2;
A2: dom s1 = dom (SCM-VAL * SCM-OK) by CARD_3:9
.= SCM-Memory by AMI_2:27 ;
now :: thesis: for x being set st x in dom s1 holds
s1 . x in f . x
end;
then s +* s1 is SCM+FSA-State by A1, A2, PRE_CIRC:6, XBOOLE_1:7;
hence s +* s1 is SCM+FSA-State ; :: thesis: verum