Pro PHP- Patterns, Frameworks, Testing and More

CHAPTER 7 ■ REFLECTION API^81

In Listing 7-8, you may replace the print_r calls with whatever way you wish to render the

result data. This could be anything from echo calls to a full-blown template engine. In any case,

the data is there, and it’s loaded from plug-ins.

Currently, you need to include each plug-in file you wish to load. In Chapter 9, which

introduces the Standard PHP Library (SPL), you will learn how to use class autoloading, so you

no longer need to include your plug-ins manually. The result will be an extremely easy-to-manage,

upload-and-go plug-in system.

Parsing Reflection-Based Documentation Data

In the previous chapter, I explained how doccomments are stored along with the program and

promised to tell you how to access that data using reflection. Accessing the doccomment data

is the easy part, and we’ll get to that, but once you have the comment data, you will need to be

able to parse it into a usable format. So, let’s first look at how comments can be parsed.

Installing the Docblock Tokenizer.

You can parse docblock comments by using the docblock tokenizer. However, installing the

tokenizer can be tricky.

The instructions here assume you have a working pecl command and are using a Unix,

Linux, or Mac OS X system. The installation should, however, work similarly on Windows systems.

Start by installing the docblock pecl extension. Execute the following command from an

administrative account:

pecl install docblock

By the time this book is published, a stable version of the docblock package should be

available. However, if it isn’t, you will see a warning like the following:

Failed to download pecl/docblock within preferred state "stable", latest release

is version 0.2.0, stability "alpha", use "channel://pecl.php.net/docblock-0.2.0"

to install

In this case, use the full-channel URL the command returns to you, and rerun the install

command in this form:

pecl install channel://pecl.php.net/docblock-0.2.0

If all went well, you now have the docblock tokenizer installed. You can confirm it is

functioning correctly with the following command:

php -i |grep DocBlock

You should then see the following result (if it is functioning correctly):

DocBlock Tokenizer support => enabled

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