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PACKAGE Screen IS
------------------------------------------------------------------
--|
--| Procedures for drawing pictures on ANSI Terminal Screen
--|
--| Author: Michael B. Feldman, The George Washington University
--| Last Modified: July 1995
--|
------------------------------------------------------------------
 
  -- constants; the number of rows and columns on the terminal
 
  Screen_Depth : CONSTANT Integer := 24;
  Screen_Width : CONSTANT Integer := 80;
 
  -- subtypes giving the ranges of acceptable inputs
  -- to the cursor-positioning operation
 
  SUBTYPE Depth IS Integer RANGE 1..Screen_Depth;
  SUBTYPE Width IS Integer RANGE 1..Screen_Width;
 
  PROCEDURE Beep;
  -- Pre:  None
  -- Post: Terminal makes its beep sound once
 
  PROCEDURE ClearScreen;
  -- Pre:  None
  -- Post: Terminal Screen is cleared
 
  PROCEDURE MoveCursor (Column : Width; Row : Depth);
  -- Pre:  Column and Row have been assigned values
  -- Post: Cursor is moved to the given spot on the screen
 
END Screen;