rInArea()

         Determines if the mouse is on a zone of the screen

    Syntax:

         rInArea( nY1, nX1, nY2, nX2 ) -> lEst.

         nY1, nX1, nY2, nX2 : The coordinates of the zone.

    Description:

         Determines if the mouse cursor is inside a zone of the screen

    Return:

         A logic value indicating if is inside of the specified zone.

    Example:

         If rInArea ( 10, 10, 12, 20 )
           Warning ( "Mouse ok" )
         EndIf