Here is curry in php 5.3

  function curry(){
    $args = func_get_args();
    $fn = array_shift($args);
    return function() use(&$fn, &$args) {
        $nargs = func_get_args();
        foreach($nargs as $narg) $args[] = $narg;
        return call_user_func_array($fn, $args);
    };
  }

  $add20 = curry(function($a, $b){return $a + $b;}, 20);

  echo $add20(5); #25

Both of our implementations have broken this. Damn you, Javascript this.

In principle, these two lines of code should always produce the same result:

  foo.bar(1,2)

and

  foo.bar(1)(2)

And they won't necessarily in our case, if the function uses this.