PHP example on variable variables

gistfile1.aw

<?php

function myForm($a, $b, $c, $d) {
// .. suppose the function receives variables called a, b, c, d

foreach (array('a', 'b', 'c', 'd') as $key) {
   $form[$key] = array(
      '#type' => 'hidden',
      '#value' => $$key,
   );
}

// without variables variables you have to
$form['a'] = array(
  '#type' => 'hidden',
  '#value' => $a,
);
// and 3 more times

}

/*
This is real code I wrote once and I don't see anything wrong with it.

Can be solved without variable variables:
1) change function prototype (receive array of variables keyed by their names instead of list of arguments)
what if your function is called from 300 places and you really don't want to change it?

2) create another array keyed by variable names and use that in cycle
$tmp = array('a' => $a, 'b' => $b);
why should I create another copy of variables when I can solve it using native language features?

*/