array_undot() helper functon

helpers.php

<?php

function array_undot($dottedArray, $initialArray = [])
{
    // to make it recursive:
    $dottedArray = array_dot($dottedArray);
    
    foreach ($dottedArray as $key => $value) {
        array_set($initialArray, $key, $value);
    }

    return $initialArray;
}