It strikes me odd that both functions are performing supposedly identical operation, however both are doing it differently when it comes to identifying whether a form element has a valid child name.
function element_child($key) {
return !isset($key[0]) || $key[0] != '#';
}function element_children...
if ($key === '' || $key[0] !== '#')
...mainly !isset($key[0]) versus ($key === '') and $key[0] != '#' versus $key[0] !== '#'.
Unfortunately i fail to grasp the subtle differences between the two versions, hence the post. Thanks in advance.