<?php

/**
 * This class is the base class for all symbols that are of the type "function".
 * Typically the textual representation of a function consists of two or more letters.
 */
abstract class Forminator_Calculator_Symbol_Function_Abstract extends Forminator_Calculator_Symbol_Abstract {

	/**
	 * This method is called when the function is executed. A function can have 0-n parameters.
	 * The implementation of this method is responsible to validate the number of arguments.
	 * The $arguments array contains these arguments. If the number of arguments is improper,
	 * the method has to throw a Exceptions\NumberOfArgumentsException exception.
	 * The items of the $arguments array will always be of type int or float. They will never be null.
	 * They keys will be integers starting at 0 and representing the positions of the arguments
	 * in ascending order.
	 * Overwrite this method in the concrete operator class.
	 * If this class does NOT return a value of type int or float,
	 * an exception will be thrown.
	 *
	 * @param  (int|float)[] $arguments
	 *
	 * @return int|float
	 */
	abstract public function execute( $arguments );

}