Question

If I have a class Foo which extends class Bar, and an instance of Bar, is there anyway to use that instance of Bar to ‘populate’ a new instance of Foo?

Essentially, I am only able to retrieve Bar, but I want to use Foo in my code as it gives me lots of additional methods.

I saw quite a few solutions come up to similar questions but they all seemed to be python or c#.

I cant use ReflectionClass::newInstanceArgs as I cant access the data that went in to the constructor of Bar to create it in the first place.

Answer 1

There is no built-in way to easily do what you want to. The interfaces of these classes must be redesigned a bit. Perhaps something like:

<?php
class Bar
{
    ...
}

class Foo extends Bar
{
     public static function fromBar(Bar $bar)
     {
         $foo = new self();
         ... (copy data here) ...

         return $foo;
     }
}

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