

   MMeennuu IInntteerraaccttiioonn FFuunnccttiioonn

        menu(choices, graphics = FALSE, title = "")

   AArrgguummeennttss::

    choices: a character vector of choices

   graphics: a logical indicating whether a graphics menu
             should be used.  Currently unused.

      title: a character string to be used as the title of the
             menu

   DDeessccrriippttiioonn::

        `menu' presents the user with a menu of choices
        labelled from 1 to the number of choices.  To exit
        without choosing an item one can select `0'.

   VVaalluuee::

        The number corresponding to the selected item, or 0 if
        no choice was made.

   EExxaammpplleess::

        switch(menu(c("List letters", "List LETTERS")) + 1,
               cat("Nothing done\n"), letters, LETTERS)

