PHP Recursive Functions

In this chapter you will learn:

1. What is a recursive function
2. How to write recursive functions
3. Example - A PHP recursive function

Description

A recursive function is a function which call itself.

How

Here's a quick overview of how a recursive function operates:

The recursive function is called by the calling code If the base case is met, the function does required calculation, then exits.

Otherwise, the function does required calculation, then calls itself to continue the recursion.

Example

Here is an example to calculate factorials:

<?PHP/*  j a  v  a2 s  . c  o  m*/
function factorial($number) { 
        if ($number == 0) return 1; 
        return $number * factorial($number-1); 
} 

print factorial(6); 
?>

The code above generates the following result.

Next chapter...

What you will learn in the next chapter:

1. What is PHP Anonymous Functions
2. Why do we need Anonymous Functions
3. Syntax to create anonymous functions
4. Example - creates an anonymous function dynamically based on the value of a variable

PHP Function

PHP Function Create

PHP Function Parameter

PHP Function Default Parameters

PHP Variable Length Parameter

PHP Function Reference Parameter

PHP Function Return

PHP Return Reference

PHP Variable Scope in Functions

PHP Global Variables

PHP Recursive Functions

PHP Anonymous Function

PHP static variable