Get the stack to which a control or a card belongs
This function is to obtain the long id of the stack to which a control or a card belongs. The parameter is a reference to a control or a card.
function myStack pLongId
if there is a pLongId then
put the long id of pLongId into pLongId
return the word (wordOffSet("stack", pLongId)) to - 1 of pLongId
else return empty
end myStack