Object-oriented Software in Ada 95

Case study: Design of a game 133
Current_State := Play; Person := Black; --Black starts
Display( The.Reversi );
while Current_State = Play loop
Now_Playing( The.Reversi, Person );
--Initial board
--Playable game
--set player
loop
--Get move
Get_Move(The.Contestant(Person), X, Y);
Move_Is:=Check_Move(The.Reversi, X, Y);--Validate
exit when Move_Is=Ok or Move_Is=Pass; --OK
end loop;
Add( The.Reversi, X, Y, Move_Is );
--Add move to board
Display( The.Reversi ); --Display new board
Current_State := Status( The.Reversi ); --State of play is
if Current_State = Play then
case Person is
when Black => Person := White;
when White => Person := Black;
end case;
end if;
end loop;
--Is still playable
--next player
--Next move
Announce( The.Contestant(Person), Current_State ); --Result
end Play;
end Class_Game;
9.5.1 Running the program
Then to run the game the following procedure is used to send the message Play to an instance of the class Game.
with Class_Game;
use Class_Game;
procedure Main is
A_Game : Game;
begin
Play( A_Game );
end Main;
9.5.2 Example of a typical game
A typical game might be:
© M A Smith - May not be reproduced without permission