.. _only-arrays-can-be-unpacked-in-constant-expression:

Only arrays can be unpacked in constant expression
--------------------------------------------------
 
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		Only arrays can be unpacked in constant expression: ``.
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Description
___________
 
``...`` may be used on both arrays and ``Traversable`` objects, but within a static constant expression, this operator only works on arrays, and cannot be used on objects, ``Traversable``  or not.

Example
_______

.. code-block:: php

   <?php
   
   const A = 2;
   
   function foo($a = [...A]) {
       print_r($a);
   }
   
   foo();
   
   ?>

Solutions
_________

+ Rewrite the expression without the ``...`` operator.
+ Convert the object into an array.

Related Error Messages
______________________

+ :ref:`only-arrays-and-traversables-can-be-unpacked`