Logging a formatted Array to watchdog so it's readable. For development/debugging purposes only.

gistfile1.php

<?php
// Load up an array with variables you want to search through
$obj[] = $notification;
$obj[] = $invoice;
$obj[] = $user;
watchdog('module_name', 'Successfully Recieved Notification', array('@notification' => print_r($obj, 1)), WATCHDOG_NOTICE, 'link');