根据深度数组中任何位置存在的特定键创建唯一值列表

Question

I have an array that consists of an undetermined number of arrays, recursively (n levels deep). Each array might contain a name key. I want to create a unique list of those values.

Example

Suppose the array is:

$bigArray = array(
    'name'=>'one', 
    'something'=>array(
        'name'=>'two', 
        'subthing'=>array('name'=>'three')
    ), 
    'anotherthing'=>array('name'=>'one')
);

The expected result would be:

$uniques = array('one', 'two', 'three') // All the 'name' keys values and without duplicates.

Here's a fiddle of my attempt.

My approach was using array_walk_recursive passing a $uniques array as reference, and allowing the function to update that value:

$uniques = array();

function singleOut($item, $key, &$uniques) {
    if ($key == 'name' && !in_array($itm,$uniques,true) )
        $uniques[] = $item;
}

array_walk_recursive($bigArray, 'singleOut', $uniques);

However, it's not working for me.

Answer 1

You could use also array_unique on this one too. Example:

$uniques = array();
array_walk_recursive($bigArray, function($val, $key) use (&$uniques){
    if($key == 'name') {
        $uniques[] = $val;
    }
});

$uniques = array_unique($uniques); // unique values