void id_list()
{
	/* <id list>		-> <ident> #read_id {, <ident> #read_id} */
	expr_rec in_var;
		
	in_var = ident();
	read_id(in_var);

	while (next_token() == COMMA) {
		match(COMMA);
		in_var = ident();
		read_id(in_var);
	}
}