Untitled

<?php

$users = array(
  "pierre"  => "admin",
  "henri"   => "peon",
  "patrick" => "admin",
  "jack"    => "anonymous",
  "didier"  => "anonymous"
);

$finished = false;
while($finished == false) {
  $admin_user = array_search('admin', $users);

  if($admin_user != false) {
    echo("Admin user: $admin_user\n");
    unset($users[$admin_user]);
  }
  else {
    $finished = true;
  }
}

var_dump($users);