Introduction

In this chapter we will consider recipes that take advantage of PHP's functional programming capabilities. Functional, or procedural, programming is the traditional way PHP code was written prior to the introduction of the first implementation of object-oriented programming (OOP) in PHP version 4. Functional programming is where program logic is encapsulated into a series of discreet functions, which are generally stored in a separate PHP file. This file can then be included in any future scripts, allowing the functions that are defined to be called at will.