/** * Returns list of variables defined in the expression * * @param string $ps_expression * @return array */ public static function getVariableList($ps_expression) { $o_exp = new ExpressionParser(); if ($o_exp->tokenize($ps_expression)) { } $va_vars = array(); while ($va_token = $o_exp->getToken()) { if ($va_token['type'] == EEP_TOKEN_VARIABLE) { $va_vars[] = $va_token['varname']; } } return $va_vars; }