[UPHPU] require_once vs. class_exists

[Scott Mattocks]

Rusty Keele wrote:
> Hi,
> 
>   Which is a better approach to use:
>   
>   1. require_once('path/to/class.php');
> 
>   or
> 
>   2. if(!class_exists('path/to/class.php')) require('path/to/class.php');
> 
>   I have been using the first approach in all my files where I need to instantiate a specific class, but I am wondering if the second approach is more efficient?  Are there any benefits to using the second approach - such as less caching of objects - or do these two statements do the same thing?

It depends on which version of PHP you are using. require_once was not 
very efficient in PHP 4 and early versions of PHP 5. I believe it has 
been fixed in later versions of PHP 5.

On a side not, you are passing a file path to class_exists. That is 
incorrect. You should pass the class name.

On another side note, require, include, require_once and include_once 
are language constructs not functions. You don't need the () and some 
would tell you that it is incorrect to add them.

Scott Mattocks