-- screen.ads
-- Primitive ANSI Terminal Screen Controls
-- *** Specification ***
-- Debora Weber-Wulff, 29.10.97, adapted from
--        "Software Construction and Data Structures", Michael B. Feldman

PACKAGE Screen IS
    
    ScreenHeight : CONSTANT Integer := 24;
    ScreenWidth  : CONSTANT Integer := 80;
    
    SUBTYPE Height IS Integer RANGE 1 .. ScreenHeight;
    SUBTYPE Width  IS Integer RANGE 1 .. ScreenWidth;
 
    PROCEDURE Beep; 
    
    PROCEDURE ClearScreen;
                      
    PROCEDURE MoveCursor (Row    : IN Height := 1;
                          Column : IN Width  := 1);
        
END Screen;