

          lvarpop var [index [string]]
               The lvarpop command pops (deletes) the element indexed
               by index from the list in the variable var.  If index
               is omitted, then 0 is assumed.  If string, is
               specified, then the deleted element is replaced by
               string. The replaced or deleted element is returned.
               Thus ``lvarpop argv 0'' returns the first element and
               sets argv to contain the remainder of the string.
