Online PHP editor | output for KGaFu

@ 2015-10-05T03:01:34Z

<?php

$lastmonday = strtotime('last monday of this month');

  $lmonday = date('Y-m-d',$lastmonday);
 
  
$firstday = strtotime('first day of this month');

  $fday = date('Y-m-d',$firstday);
  
  
       $d1 = new DateTime($lmonday);
       $dd1 =   $d1->format('Y-m-d');
       $d2 = new DateTime($fday);
       $dd2 =   $d2->format('Y-m-d');
     
       $period_serv = $dd1->diff($dd2);
       $theperiod = $period_serv->format('%a');
     
       echo $theperiod;

Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6: Fatal error: Uncaught Error: Call to a member function diff() on string in /in/KGaFu:18 Stack trace: #0 {main} thrown in /in/KGaFu on line 18
Process exited with code 255.
Output for 5.6.0 - 5.6.28: Fatal error: Call to a member function diff() on string in /in/KGaFu on line 18
Process exited with code 255.
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38: Fatal error: Call to a member function diff() on a non-object in /in/KGaFu on line 18
Process exited with code 255.

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