Should require_once “some file.php” ; appear anywhere but the top of the file?

Question

Is the following example appropriate for PHP\'s require_once construct?

function foo( $param )
{
    require_once \"my_file.php\" ;
    //
    // do somethin         


        

Answer 1

This is something of a religious debate.

PROS for require and include statements at the top of the file:

1. dependencies are clearly documented in a consistent reliable place.

2. increased readability/maintainability

3. OP code caching is simpler (although you could argue that this doesn't affect the developer directly)

CONS for require and include statements at the top of the file:

1. If you're doing some kind of dynamic runtime including (such as with __autoload()), a hardcoded statement at the top of the file is impossible.

2. If only one execution path in the code uses an include, having it included every time, unconditionally is a waste of resources.

3. long list of include or require statement is just noise the developer must scroll past when editing a file. Of course, a long list of dependencies can be viewed as a sign that the code should be broken up into smaller more focused pieces, so maybe you could spin this one as a PRO because it makes a code smell stand out.