fix create_and_operator error

util_new.c

@@ -85,6 +85,7 @@ cons_cell* create_op(char *op) {
 
 // todo: why need ra
 cons_cell* create_comp_operator(cons_cell* op, cons_cell* term1, cons_cell* term2, cons_cell* ra) {
+
 	cons_cell* ra_cons = create_cons_cell(ra, NULL);
 	cons_cell* term2_cons = create_cons_cell(term2, ra_cons);
 	cons_cell* term1_cons = create_cons_cell(term1, term2_cons);
@@ -103,7 +104,6 @@ cons_cell* create_atom_operator(cons_cell* table, cons_cell* var) {
 	return operator_cons;
 }
 
-// todo: why pass NULL
 cons_cell* create_union_all_operator(cons_cell* ra1, cons_cell* ra2) {
 	cons_cell* ra2_cons = create_cons_cell(ra2, NULL);
 	cons_cell* ra1_cons = create_cons_cell(ra1, ra2_cons);
@@ -121,6 +121,7 @@ cons_cell* create_union_operator(cons_cell* ra1, cons_cell* ra2) {
 }
 
 cons_cell* create_and_operator(cons_cell* ra1, cons_cell* ra2) {
+	printf("create_and_operator called \n");
 	cons_cell* ra2_cons = create_cons_cell(ra2, NULL);
 	cons_cell* ra1_cons = create_cons_cell(ra1, ra2_cons);
 	char operator[4] = "AND\0";
@@ -219,10 +220,12 @@ void print_cons_tree_helper(cons_cell *root, int indent) {
 		}
 		printf("%s", ((atom*)root->car)->val);
 		printf("\n");
-
+		// printf("one\n");
 		print_cons_tree_helper(root->cdr, indent+1);
 	} else {
+		// printf("two\n");
 		print_cons_tree_helper((cons_cell*)root->car, indent);
+		// printf("three\n");
 		print_cons_tree_helper(root->cdr, indent);
 	}
 }