unset a element of an array via reference

Answer 1

Ok, better answer I think. In order to unset , you should get a reference to the container array, then unset the element within the array;

i.e.

$value = & $this->getFromArray('type.conf');

unset  $value['host'];

Answer 2

References are not like hard-links. If you unset a reference, this will not unset the origin value.

<?php 
$a = 5;
xdebug_debug_zval('a'); // a: (refcount=1, is_ref=0), int 5

$b = &$a;
xdebug_debug_zval('a'); // a: (refcount=2, is_ref=1), int 5
xdebug_debug_zval('b'); // b: (refcount=2, is_ref=1), int 5

unset($b);
xdebug_debug_zval('a'); // a: (refcount=1, is_ref=0), int 5

Why not write a little Config class which abstracts the data (array)? Since objects are always passed by reference you won't need to handle this at your own.

class Config
{
    // ...
}

$config = new Config(array(
    'db' => array(
        'name' => 'mydatabase',
        'user' => 'root',
        'pass' => '12345',
    )
));

$config->get('db.user');
$config->set('db.user', 'newuser');
$config->unset('db.user');
//...