optionSplit is a very tricky function. It's primarily used in the menu-objects where you define properties of a whole bunch of items at once. Here the value of properties would be parsed through this function an depending on your setup you could eg. let the last menu-item appear with another color than the other.
The syntax is like this:
|*|- splits the value in parts first, middle, last.
||- splits each of the first, middle, last in subparts
- The priority is last, first, middle.
- If the middle-value is empty (""), the last part of the first-value is repeated.
- If the first- or middle value is empty, the first part of the last-value is repeated before the last value
- The middle value is rotated.
ex: first1 || first2 |*| middle1 || middle2 || middle3 |*| last1 || last 2