NYCPHP Meetup

[Dan Cech]

Adam Maccabee Trachtenberg wrote:
> On Wed, 16 Jun 2004, Dan Cech wrote:
>>The idea of variable functions and using a variable as a function name
>>is kind of weird, but can also allow you to do some cool tricks.
> 
> I actually find myself more frequently using call_user_func_array()
> than plain old call_user_func() because it allows you to more easily
> call functions with an arbitrary number of parameters.
> 
> In particular, it's super useful for object aggregation in PHP 5 when
> you invoke it within __call().

If you like call_user_func_array then you will love safe_args, I've been 
working on it with Dan Kuykendall (of phpGroupWare) as a different way 
of handling function arguments.

For example, say you had a function like:

function myfunc ($a, $b, $c)
{
   ...
}

When defining the function it allows you to define which arguments are 
mandatory and which are optional, default values for optional arguments 
and acceptable data types.

The code using safe_args would look like:

function myfunc ()
{
   $args = new safe_args();
   $args->set('a',REQUIRED,'any');
   $args->set('b',REQUIRED,'any');
   $args->set('c',REQUIRED,'any');
   $args = $args->get($func_get_args());

   ...
}

You then access each argument within the function as $args['a'], 
$args['b'], etc.

As you can see above the definition for each argument includes the name, 
the default value (or REQUIRED) and the type.

When calling the function above you could call it with:

myfunc($my_a,$my_b,$my_c);

or

myfunc(array($my_a,$my_b,$my_c));

or

myfunc(array('b'=>$my_b,'a'=>$my_a,'c'=>$my_c));

It took a little getting used to, but now I love the flexibility it 
offers, as well as the ability to enforce input validation rules with 
little effort.

If you are interested you can read more details at:

http://wiki.phpgroupware.org/index.php?page=nextgen

And view the source at:

http://savannah.gnu.org/cgi-bin/viewcvs/phpgroupware/api/core_functions.inc.php?rev=1.1.1.1.2.23&content-type=text/vnd.viewcvs-markup

Dan