Online PHP editor | output for qVYWZ

@ 2018-09-24T20:01:56Z

<?php

class ParentItem
{
}

class ChildItem extends ParentItem
{
}

class ParentManager
{
    function do_something(ParentItem $item)
    {
    }
}

class ChildManager extends ParentManager
{
    // this is the problem. how do i explain to php that 
    // ChildItem *is* a ParentItem
    function do_something(ParentItem $item)
    {
    }
}

(new ChildManager())->do_something(new ChildItem);

Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.22, 7.1.24 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
Output for 8.3.5: Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0
Output for 7.1.23: Process exited with code 137.

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