cast.double

Code example

<?php declare(strict_types = 1);

$value = (float) new \stdClass();

Why is it reported?

The expression being cast to float is of a type that cannot be converted to a float. PHP does not support casting certain types (such as objects that do not implement __toString() or other non-numeric types) to float, and attempting to do so will result in an error at runtime.

In the example above, an stdClass object cannot be cast to float.

How to fix it

Extract the numeric value from the object or expression before casting:

 <?php declare(strict_types = 1);

-$value = (float) new \stdClass();
+$obj = new \stdClass();
+$obj->value = 3.14;
+$value = (float) $obj->value;

Or ensure the expression produces a type that can be cast to float, such as int, string, or bool:

 <?php declare(strict_types = 1);

-$value = (float) new \stdClass();
+$value = (float) '3.14';