fetch.php

<?php

/**
 * Safely get a value by key from an array (without creating a notice)
 * @param array|object $array - can be an array or object
 * @param int|string|array $keys - if array, performs a deep fetch on a multidemensional array|object
 * @param mixed $default - if $keys do not exist in $array, this value is returned
 * @return mixed - The value at $keys, or else $default
 * @throws Exception if $keys is not a scalar or array
 */
if (!function_exists('fetch')) {
    function fetch($array, $keys, $default = null)
    {
        // most often, $keys will be a scalar, so a direct key check on $array should be used to maximize performance
        if (is_scalar($keys)) {
            if (array_key_exists($keys, $array)) {
                return is_object($array) ? $array->$keys : $array[$keys];
            }

            return $default;
        }

        // less often, $keys is an array, which triggers deep fetching

        if (!is_array($keys)) {
            throw new \Exception('$keys must be a scalar or an array');
        }

        foreach ($keys as $key) {
            if (array_key_exists($key, $array)) {
                $array = is_object($array) ? $array->$key : $array[$key];
            } else {
                return $default;
            }
        }

        return $array;
    }
}