33 lines
759 B
Prolog
33 lines
759 B
Prolog
:- module(cont, [reset/3, shift/1]).
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:- meta_predicate(reset(0, ?, ?)).
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reset(Goal, Ball, Cont) :-
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call(Goal),
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'$reset_cont_marker',
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'$bind_from_register'(Cont, 3),
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'$bind_from_register'(Ball, 4).
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shift(Ball) :-
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'$nextEP'(first, E, P),
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get_chunks(E, P, L),
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( L == [] ->
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Cont = cont(true)
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; Cont = cont(cont:call_continuation(L))
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),
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'$write_cont_and_term'(_, _, Cont, Ball),
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'$unwind_environments'.
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get_chunks(E, P, L) :-
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( '$points_to_cont_reset_marker'(P) ->
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L = []
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; '$get_cont_chunk'(E,P,TB),
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L = [TB|Rest],
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'$nextEP'(E, NextE, NextP),
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get_chunks(NextE, NextP, Rest)
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).
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call_continuation(L) :- '$call_continuation'(L).
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'$write_cont_and_term'(_, _, _, _).
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