Page 479 - Beginning PHP 5.3

15

Making Your Job Easier

with PEAR

Once you start creating a few PHP Web applications, you ’ ll find that your scripts often need to do
the same tasks again and again. For example, many applications require a login/logout
mechanism, and most Web applications display and process HTML forms at some point.

If you ’ ve written your applications in a modular way, using classes and functions to break them
down into specific chunks of functionality, you should find that you can reuse those classes or
functions across applications. For instance, the Member class you developed in Chapters 13 and 14
could easily be used to register, store, and retrieve members for any Web application.
Code reuse is important because it can save you hours of time. However, rather than reusing your
own code, why not reuse someone else ’ s? That way, you don ’ t even have to write the code in the
first place! This is where PEAR comes in. PEAR stands for the PHP Extension and Application
Repository, and it ’ s a big collection of high - quality, open - source code packages that you can freely
download and use in your own applications.

When using a PEAR package, make sure that you check its license. Some package licenses let you
use the package in practically any way you like; for example, you can include the code in an
application that you then sell as a product. Other licenses are more restrictive.
Each package is a separately maintained class, or set of classes, for achieving a specific goal. At the
time of writing, more than 500 packages are available, covering everything from database access
through to authentication, file handling, date formatting, networking and email, and even weather
forecasting. You can browse the full list at http://pear.php.net/packages.php . Though many
packages can function independently, a package often requires one or more other packages to do
its job. These other packages are known as dependencies of the main package.

Before starting on any new project, it ’ s a good idea to check the PEAR repository to see if there are
any packages you can incorporate into your application. You may well find that half of your job
has already been done for you, saving you a huge amount of time.

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