DevShed has posted the next part of their series looking at the "magic functions" that PHP5+ has to offer you in your development. They've already looked at ones like __call, __clone and __isset/__unset and now, with this new tutorial they've added __sleep and __wake.

Magic functions are an important part of the numerous improvements and additions that were introduced originally in PHP 5. They can be extremely handy when it comes to simplifying the execution of complex tasks. [...] In this fourth chapter I'm going to examine closely the "__sleep()" and "__wakeup()" functions, which are called automatically when an object is serialized and unserialized respectively.

In their example code they add the __sleep and __wake functions to the class they've been developing to output a string when the object is manipulated. These methods are automatically called when a serialize/unserialize function call is made on the object.