<?php

  /*
   * lvl 1 : remove all "="
   * lvl 2 : lvl 1 + remove all "or"
   */

function rec_remove ($entry, $str)
{
  $count = 1;
  while ($count > 0)
    $entry = str_ireplace($str, "", $entry, $count);
  return $entry;
}

function lvl1_filter ($entry)
{
  $entry = rec_remove ($entry, "=");
  return $entry;
}

function lvl2_filter ($entry)
{
  $entry = lvl1_filter($entry);
  return rec_remove ($entry,"or");
}

?>