Without a doubt, the PHP5/ZE2 object model is more complex than its PHP4/ZE1 predecessor. After seeing all of the feature and implementation details in this chapter, you're probably a bit overwhelmed by the volume of it all. Fortunately, the layers that make up OOP within PHP enable you to pick and choose the pieces appropriate to your task and leave the rest alone. Find a good comfort level and start working upwards in complexity; the rest will follow.
Now that all of PHP's internal data types have been covered, it's time to return to an earlier topic: the request life cycle. In the next two chapters, you'll add internal state to your extension through the use of thread-safe globals, define custom ini settings, declare constants, and offer superglobals to userspace scripts using your extension.
The PHP Life Cycle
Variables from the Inside Out
Setting Up a Build Environment
Your First Extension
Working with Arrays and HashTables
The Resource Data Type
Startup, Shutdown, and a Few Points in Between
Diverting the Stream
Configuration and Linking
Setting Up a Host Environment
Appendix A. A Zend API Reference
Appendix B. PHPAPI
Appendix C. Extending and Embedding Cookbook
Appendix D. Additional Resources