| menu {base} | R Documentation | 
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'.
menu(choices, graphics = FALSE, title = "")
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 | 
The number corresponding to the selected item, or 0 if no choice was made.
switch(menu(c("List letters", "List LETTERS")) + 1,
       cat("Nothing done\n"), letters, LETTERS)