This feature is experimental. It may be removed or changed in a future version without prior notice or deprecation.
If the given argument is already a jQuery collection (or an array of DOM elements), the first element matching these conditions is returned.
undefined if no element matches these conditions.
Also see the
The name of the layer in which to find the element.
Valid values are
An second element or selector that can be referenced as
& in the first selector:
$input = $('input.email'); up.first('.field:has(&)', $input); // returns the .field containing $input
The first element that is neither a ghost or being destroyed,
undefined if no such element was found.