Re: how include works?

Arno Kuhl wrote:

On 5/30/06, Arno Kuhl <akuhl@telkomsa.net> wrote: I understand the difference well enough, but I've never really understood the reason for having both. Is it to help find errors in sloppy coding, or is there a case where including a file more than once is desirable (and won't cause an error)?

-----Original Message----- From: chris smith [mailto:dmagick@gmail.com] Sent: 30 May 2006 02:11 To: arno@dotcontent.net Cc: php-general@lists.php.net Subject: Re: [PHP] how include works? There was more of a difference earlier on. On http://www.php.net/manual/en/function.require.php: Note: Prior to PHP 4.0.2, the following applies: require() will always attempt to read the target file, even if the line it's on never executes. Now it behaves the same way except for the failure method (require is fatal, include is not). -- I wasn't talking about the difference between require and include but rather the difference between require and require_once (or include and include_once). Why doesn't require just work the same way as require_once, because I can't see the need for require -ing the same file more than once. Possibly for someone that doesn't understand the purpose of functions, as Peter suggested, but programming languages don't generally go out of their way to cater for people who don't understand basic programming concepts.

OOP. file "b.php" <?php require('a.php'); class b extends a { } ?> file "c.php" <?php require('a.php'); class c extends a { } ?> ... Using both class "c" and "a" within the same request would cause an error because both are require'ing a.php. This situation might come up when developing or using any sort of API - your base methods (load, save, update, delete etc) are in "a.php" and are overridden in the subclasses. Using that API, class b might load up a user, class c might save comments to the database - you need to load the user to check permissions before you save to the database. -- Postgresql & php tutorials http://www.designmagick.com/