If you’re an eager PHP developer who wants to have at your disposal a quick guide that shows you how to work with the most relevant magic functions provided by PHP 5, then this series of articles might be what you’re looking for. In this fifth part of a seven-part tutorial on magic functions, we'll briefly review the sleep and wakeup functions, and then tackle the clone function.
Undoubtedly, the release of PHP 5 quite some time ago brought with it a significant advance in the way that web applications are developed nowadays. This is despite the high level of backward compatibility it maintains with its venerable predecessor, PHP 4.
Certainly it’s not breaking news that PHP 5 comes packaged with a robust object model and a whole new set of functions and time-saving libraries, not to mention its handy exception mechanism, which allows it to handle errors and exceptional events in a truly efficient and elegant way.
Of course, when I use the term “functions,” I’m not talking about only the common ones that perform specific tasks such as reading data from a file or applying a filter to a supplied variable. I'm also referring to the magic ones; that is, the functions that have no a concrete implementation by default and are called automatically by the PHP engine in response to certain events.
The trio comprised of the “__set()”, “__get()” and “__call()” methods offer a classic example of magic functions that are used when developing object-oriented PHP applications, but there are a few others that certainly deserve deeper analysis as well.
And speaking of magic functions, you’ll surely recall that I left off the last article discussing the use of the “__sleep()” and “__wakeup()” methods, which are invoked by the PHP interpreter when serializing and unserializing a specified object.
Though these methods were only responsible for echoing to the screen some basic messages when called, the examples developed in the aforementioned tutorial should give you a clear idea of how to use them in a more helpful manner.
Though, as I said before, there are other magic functions that are worth exploring in detail as well. So, with that goal in mind, in this fifth part of the series I’m going to take a closer look at the “__clone()” method, which as its name suggests, is called behind the scenes when using the “clone” PHP keyword.
So, now it’s time to leave the theory behind us and start learning now to use this brand new magic function. Let’s get started right away!
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