': return $left_operand > $right_operand; case '>=': return $left_operand >= $right_operand; case '!=': return $left_operand !== $right_operand; case 'contains': if ( is_array( $left_operand ) && is_string( $right_operand ) ) { return in_array( $right_operand, $left_operand, true ); } return strpos( $right_operand, $left_operand ) !== false; case '!contains': if ( is_array( $left_operand ) && is_string( $right_operand ) ) { return ! in_array( $right_operand, $left_operand, true ); } return strpos( $right_operand, $left_operand ) === false; case 'in': if ( is_array( $right_operand ) && is_string( $left_operand ) ) { return in_array( $left_operand, $right_operand, true ); } return strpos( $left_operand, $right_operand ) !== false; case '!in': if ( is_array( $right_operand ) && is_string( $left_operand ) ) { return ! in_array( $left_operand, $right_operand, true ); } return strpos( $left_operand, $right_operand ) === false; } return false; } }