25 lines
515 B
Text
25 lines
515 B
Text
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% "Hello World" in Mercury.
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:- module hello.
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:- interface.
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:- import_module io.
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:- pred main(io::di, io::uo) is det.
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:- implementation.
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main(!IO) :-
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io.write_string("Hello, world\n", !IO).
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:- pred filter(pred(T), list(T), list(T), list(T) ).
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:- mode filter(in(pred(in) is semidet), in, out, out ) is det.
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filter(_, [], [], []).
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filter(P, [X | Xs], Ys, Zs) :-
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filter(P, Xs, Ys0, Zs0),
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( if P(X) then Ys = [X | Ys0], Zs = Zs0
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else Ys = Ys0 , Zs = [X | Zs0]
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).
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