Access a specific element of a nested array

array_access.php

<?php
/**
 * Return the reference to an element/subarray
 * of an array, specified by a key array
 * 
 * @param  array &$array Array to access by reference
 * @param  mixed $keys   Array of the keys
 * @return mixed         Reference to the match
 */
function &array_access(&$array, $keys) {

    // If there are keys left to walk down
    // a nested array
    if ($keys) {

        $key = array_shift($keys);

        // Get and return the reference to the
        // subarray with the current key
        $sub = &array_access(
            $array[$key],
            $keys
        );

        return $sub;
    } else {

        // Return the match
        return $array;
    }
}

// Usage
$array = [];
$keys  =['houses', 'ocean_view', 'state'];

// Here we're accessing the array match
// by reference
$reference = &array_access($array, $keys);
$reference = 'Oregon';

// But we might also just return the value
$value = array_access($array, $keys);
echo $value;

$value = 'Ibiza';
print_r($array);
?>