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Date: Mon, 13 Nov 2006 11:42:17 +0100
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Subject: Feature-Request - Macros
From: phpinternals@thunder-2000.com (Mathias Bank)

Hallo,

you know, that there was often a discussion about a "ifsetor" function. 
I want to generalize this discussion. If you know LISP, there is a 
fantastic macro function which allows you to generate own syntax (not a 
c macro function, which is really bad). It would be fantastic, if php 
could implement such a macro function. One example (for ifsetor): you 
could define

macro ifsetor($param1, $param2) {
    return "if (isset($param1)) return $param1; else return $param2;
}

use: $test = ifsetor($_GET["blubb"],null);

All you have to do is to not execute the parameters given in the macro 
parameter list. Instead, you have to evaluate the return statement and 
then to execute this statement.

In this way, all discussions about ifsetor (or anything like this) could 
be avoided.

The macro function could even be extended to allow new blocks, but then 
we have to extend the syntax to allow reference to the body. In this 
way, I always extend the syntax of the parameter data: only variables 
would be matched.

macro foreachkey($array as $key, :body $body) {
   return "foreach ($array as $key=>$__dev0) {
        $body
      }";
}

know, you can call
$secondArray = array();
foreachkey($myArray as $myKey) {
     $secondArray[] = $myKey;
}

this would be extended to
foreach ($myArray as $myKey=>$__dev0) {
   $secondArray[] = $myKey;
}

and this code will be executed.

As you see, with this macro functions, it could be achieved any 
individual syntax. It would be a pleasure, if php could support it. It 
could shorten a lot of code.

Mathias