theorem :: VALUED_2:94

for X, X1, X2 being set
for Y, Y1, Y2 being complex-functions-membered set
for f being PartFunc of X,Y
for f1 being PartFunc of X1,Y1
for f2 being PartFunc of X2,Y2 holds (f <//> f1) <##> f2 = (f <##> f2) <//> f1