Description:
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Interpreter produces `PHP Fatal error:  Constant expression contains invalid operations in…` because of explicit const value type cast.

But implicit is allowed and works as expected.

Yes, I undestand difference between `+` and `(int)` that `int` will cast to integer and drop past-float part. But question why that's now allowed is still present.

Casting plain value rather than array value doesn't work too. Even if you cast integer to integer.

Test script:
---------------
class Barcode
{
    const BARCODE_TYPES = [
        (int)\Stickers::BARCODE_TYPE_MEGAORDER,
        +\Stickers::BARCODE_TYPE_SHOP_ORDER,
    ];
}

Expected result:
----------------
All is OK and array value became int casted.

Actual result:
--------------
PHP Fatal error:  Constant expression contains invalid operations in…