Description:
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I have this array filled with all kinds of types.
Today I used a DateTime object in that array for the first time.

In my code there is this line:
$aUniqueValues = array_unique($aValues);

and there is an fatal error now:
Catchable fatal error: Object of class DateTime could not be converted to string in MyClass.php on line 149

I can't find in the documentation
http://php.net/manual/en/function.array-unique.php
how to catch that error.


Test script:
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$aValues = array();

$now = date('Y-m-d H:i:s');
$aValues['test1'] = $now;
$aValues['test2'] = DateTime::createFromFormat('Y-m-d H:i:s', $now);

$aUniqueValues = array_unique($aValues);


Expected result:
----------------
I would expect no fatal error, but a normal unique array.

I think, it is a bit strange that I can make a string out of a DateTime object, and that the code behind array_unique can't do that.