curry.php

<?php
function curry($f, $arg1) {
  $args = func_get_args();
  array_shift($args);
  return function () use ($f, $args) {
    $callArgs = func_get_args();
    $args = array_merge($args,$callArgs);
    return call_user_func_array($f,$args);
  };
}
$f = curry('\\substr','Hallo Welt');
echo $f(2,-2) . PHP_EOL;