[Coding Standards] (require|include)_once not allowed

The proposed standard states:

*_once including of files not allowed include/require/require_once/include_once is not allowed for loading class files except in the "load all classes for beginners" file. Instead, class_exists() with the optional second parameter should be used. Instead of: <?php require_once 'PEAR2/OtherPackage.php'; ?> this should be used: <?php if (!class_exists('PEAR2_OtherPackage', true)) {

      throw new PEAR2_PackageName_Exception('Dependency PEAR2_OtherPackage not found');

} ?> This allows packages to work unmodified both inside a phar archive and extracted to disk, and provides end users a much more flexible choice of how to load classes.

While "phar" is wonderful, I am wary of writing a general coding standard with one particular tool in mind. This would be like saying "don't use function X because a particular IDE doesn't work well with it". Can anyone here tell me why or how the class_exists() + throw() solution is a "more flexible choice" for class loading, so much so that require_once() should be prohibited? This seems like another candidate for "recipe" or "practice" to me, not a rule by which package acceptance can be denied. -- Paul M. Jones <http://paul-m-jones.com> Solar: Simple Object Library and Application Repository for PHP5. <http://solarphp.com> Join the Solar community wiki! <http://solarphp.org> Savant: The simple, elegant, and powerful solution for templates in PHP. <http://phpsavant.com>