#22216 [Com]: Named Arguments

[jason at godsey dot net]

 ID:               22216
 Comment by:       jason at godsey dot net
 Reported By:      tim dot lokot at printsoft dot com
 Status:           Open
 Bug Type:         Feature/Change Request
 Operating System: All
 PHP Version:      4.3.0
 New Comment:

<?php
// Missing named arguments work around..
// Set the default/REQUIRED var to something unlikely.

define("REQUIRED", "_^_-" . rand(1000000,99999999) . "-" . time());

function parseRequired (&$defaults, &$args)
{
 foreach ($defaults as $key=>$value) {
   if(!isset($args["$key"])) {
     if ($value == REQUIRED) {
        $backtrace = debug_backtrace();
        $function = $backtrace[1]["function"];
        throw new Exception("function: $function var: \$$key not
defined");
     }
     $args[$key] = $value;
   }
 }
 return 0;
}

function debugging ($args)
{
 $defaults = array(
   "name"=>"Lanny Jason Godsey",
   "text"=>"This is the default text!",
   "date"=>REQUIRED
 );
 parseRequired($defaults, $args);
 print "($args[date]) Welcome $args[name], text entered:
$args[text]\n";
}

debugging(array("name"=>"L. Jason Godsey","date"=>date("Y-m-d")));

?>


Previous Comments:
------------------------------------------------------------------------

[2003-02-13 16:59:47] tim dot lokot at printsoft dot com

I know this can be accomplished in other way and also know this has
been brought up before, but they are messy and require code from the
developer to handle this which seems to go against the php ethos of
easy and fast to develop.

If named arguments could be passed to functions and actually processed
by the php parser, then this would be really great.  Especially where
function prototypes have default values in them and you only want to
set one of them.  The proposed syntax would be something like this:

function foo ($var1="some value", $var2, $var3="some other value")
{
  // function code
}

then to call the function would be like this

foo (var2:="value for argument 2 only");

This would also be great if this feature would extend to the existing
functions in the extensions as well.

mail (to:="[EMAIL PROTECTED]", message:="no message", subject:="subject");

This in my opinion makes the function calls more readable in some
circumstances, particularly when you have to keep going back to the
prototype to figure out what the order of the arguments is.  It's kind
of self documenting really when you look at code written in this way.

Bug #2285: default arguments skipping
(http://bugs.php.net/bug.php?id=2285) was filed with a similar
suggestion and the solution suggested was to use associative arrays.

Becuase it was never explained in any of the other reports as to why
this wasn't going to be implemented, why the above not more preferable
to have than always have to implement the same code this:

function foo ($args)
{
  // Named Argument Checks
  $var1 = "some value";
  $var3 = "some other value";

  foreach ($args as $key => $value)
  {
    $$key = $value;
  }

  // Do function code here
}

foo (array ("var2"=>"some other value again","var1"=>"variable 1"));


Surely forcing developers into using this messy syntax goes against one
of the main strengths of php which is simple code that's easy to read,
understand and develop.

I'm in no wasy saying the above code was hard, just the first example
of named arguments seems to fit more into the php way than the second
example.

If this is to be rejected like the other requests for it, can you
please provide a reason why the array method is more preferable?

------------------------------------------------------------------------


-- 
Edit this bug report at http://bugs.php.net/?id=22216&edit=1