public void checkType(Symtab st) {
		if (oa != null) {
			oa.setScope(scope);
			oa.checkType(st);
		} else if (id1 != null) {
			id1.setScope(scope);
			id1.checkcontext(st);
			SymtabEntry id1Entry = st.lookup(id1.toString());
			if (!id1Entry.getType().equals("message")) {
				SymtabEntry id1TypeEntry = st.lookup(id1Entry.getType());
				if (id1TypeEntry == null)
					Main.error(id1.toString() + " does not have attributes");
			}
		}
	}