XPmenu()
 A menu Command
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   Function:   XPmenu()

               This function look's quite like XPmouseMenu(), but uses some
               features of this section which make it different. Inkey() is
               handled by XPinkey(), colors by XPdisplay(). Nice menus with
               Hi-Lighted choices are possible, and, of course, the Mouse is
               supported.

   Syntax:     XPmenu(aMenu,nDefault) --> nMenuChoice

   Arguments:  aMenu is an Array of choices, formatted as follows:
               { { nRow, nCol, cChoice } .. }.
               nDefault defaults to 1

   Returns:    The menu choice or 0 on Escape.

   Usage:      XPalert() uses XPmenu() for the Choice prompting.