obj T1 =  integer and real and string and boolean;
obj T2 =  integer and real and string and boolean;
obj T3 =  T1 and T2;

val T:T3 = { {1, 2.5, "xyz", true}, {2, 3.5, "abc", false} };
val T':T3 = [ {1, 2.5, "xyz", true}, {2, 3.5, "abc", false} ];	(* ERROR *)