Property :: position - Select an instance relative to the current selection

The function allows reading an instance relative to the currently positioned instance. Thus the function allows positioning to the next instance in the collection ( position(1) ) or the previous instance ( position(-1) ).

Calling the function with offset 0 (( position(0) )), the function does not change selection, when an instance had been located before. When no instance is located in the property handle, the function positions the first instance in the collection.

When a filter has been set for the property handle, the function skips instances not fulfilling the filter condition.

When being executed successfully the positioned property handle will be returned. In case of an error or when the requested instance is not available, the function throws an error.