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run code in 200+ php & hhvm versions
Bugs & Features
<?php $arr = array( "mac_address"=>"989096e255a1", "status" =>"Known", "attributes" => array( "Owner"=>"rogue@wpi.edu", "IPAM-Hostname"=>"dresden.wpi.edu", "IPAM-AdminState"=>"OK", "IPAM-NAS-IP-Address"=>"", "IPAM-NAS-Port-ID"=>"", "IPAM-RADIUS-VLAN"=>"", "IPAM-TimeStamp"=>"2017-07-11 11:18:33 EDT", "Guest Role ID"=>"", "MAC-Auth Expiry"=>"", "Username"=>"" ) ); $filtered = array_filter($arr, function($var){return is_null($var);} ); print_r($filtered);
Output for 5.6.30
Array ( )