php constant in oops being changed by the class object -

today reading constant in oops , got confused piece of code na dcould not make out reason code given below:

<?php class myclass1 {     const id=1;     private $name;      public function get_name()     {         return $this->name ."<br>";     }      public function set_name($setname)     {         $this->name=$setname;     } }  $myclass1_object = new myclass1();  $myclass1_object->id=2;  print("<br>".$myclass1_object->id); ?> 

i want know reason how can constant variable i.e const id=1 being changed the class object i.e $myclass1_object->id=2; , in print statement updated value i.e 2.

if try access undefined object property php creates you:

$obj = new stdclass();  $obj->hello = 'world'; 

so created field id when try access constant such way. try print constant value @ end of script:

echo myclass1::id; 

and should still 1