What happens when mymodule is enabled, but because of the registry (or even
in D6, the "file" argument in hook_menu()) is not loading the function you assume
exists just because mymodule is enabled (and module_exists('mymodule') returns
TRUE?

I guess function_exists() would be path dependent now? Please correct me.

On Sun, Jun 22, 2008 at 5:46 PM, Larry Garfield <larry@garfieldtech.com> wrote:
Come Drupal 7, you'll want to use drupal_function_exists() specifically so
that it can lazy-load the function if needed.  I suppose that's a strike in
favor of using function_exists() for now so that your logic is already setup
for that.

On Sunday 22 June 2008 4:36:46 pm Greg Knaddison - GVS wrote:
> Hi,
>
> In building some contrib modules that interact with other modules I
> often find myself writing something like:
>
> if (module_exists('module_name')) {
>   $foo = module_name_api_function($bar);
> }
>
> This seems to be pretty common across core and contrib.  I'd even call
> it standard.
>
> Another option would be:
>
> if (function_exists('module_name_api_function')) {
>   $foo = module_name_api_function($bar);
> }
>
> The benefit of the second format is that if/when module_name's
> maintainer decides to rewrite module_name and change all their
> functions then my module may simply stop interacting with it rather
> than failing on a function not found error.
>
> The benefit of the first format is that it fails quickly and is likely
> to generate a bug report with a very clear solution.
>
> Thoughts?
>
> Thanks,
> Greg

--
Larry Garfield
larry@garfieldtech.com



--
Khalid M. Baheyeldin
2bits.com, Inc.
http://2bits.com
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