4569fca292
git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@1858 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
67 lines
1.3 KiB
Plaintext
67 lines
1.3 KiB
Plaintext
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:- object(buffer).
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:- threaded.
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:- public([put/1, get/1]).
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:- private(item/1).
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:- dynamic(item/1).
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put(N) :-
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( N > 0 % wait until the previous item is consumed
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-> NP is N - 1, threaded_wait(consumed(NP)) % (except for the first item!)
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; true
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),
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assertz(item(N)),
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sender(Sender),
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writeq(Sender), write(' wrote item '), write(N), nl,
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threaded_notify(produced(N)). % notify consumer that a new item is available
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get(N) :-
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threaded_wait(produced(N)), % wait until an item is available
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retract(item(N)),
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sender(Sender),
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writeq(Sender), write(' read item '), write(N), nl,
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threaded_notify(consumed(N)). % notify producer that the item was consumed
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:- end_object.
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:- object(producer).
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:- public(run/1).
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run(N) :-
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run(0, N).
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run(N, N) :- !.
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run(M, N) :-
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M < N,
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random::random(1, 5, Random), % simulate a variable amount of
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thread_sleep(Random), % time to produce a new item
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buffer::put(M),
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M2 is M + 1,
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run(M2, N).
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:- end_object.
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:- object(consumer).
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:- public(run/1).
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run(N) :-
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run(0, N).
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run(N, N) :- !.
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run(M, N) :-
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M < N,
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random::random(1, 5, Random), % simulate a variable amount of
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thread_sleep(Random), % time to consume an item
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buffer::get(M),
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M2 is M + 1,
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run(M2, N).
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:- end_object.
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