theorem Th28:
 UsedILoc Macro i = UsedIntLoc i
proof
  rng Macro i = {i, halt SCM+FSA} by COMPOS_1:67;
 hence UsedILoc Macro i
   = union { UsedIntLoc j : j in {i, halt SCM+FSA}}
  .= UsedIntLoc i \/ UsedIntLoc halt SCM+FSA from SUBSET_1:sch 6
  .= UsedIntLoc i by Th13;
end;
