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81 lines
1.9 KiB
Mathematica
81 lines
1.9 KiB
Mathematica
%---------------------------------------------------------------------------%
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% vim: ts=4 sw=4 et ft=mercury
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%---------------------------------------------------------------------------%
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%
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% solver_build_call.m
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% Ralph Becket <rafe@cs.mu.oz.au>
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% Tue Oct 18 15:30:39 EST 2005
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%
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% This detects a bug where modes.build_call was using out-of-date versions
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% of the varset and vartypes, and then overwriting these fields in the
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% mode_info, leading to a compiler abort:
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%
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% Uncaught Mercury exception:
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% Software Error: mode analysis: rechecking extra goals adds more extra goals
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%
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%---------------------------------------------------------------------------%
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:- module solver_build_call.
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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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%---------------------------------------------------------------------------%
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%---------------------------------------------------------------------------%
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:- implementation.
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:- import_module list.
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:- import_module std_util.
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%---------------------------------------------------------------------------%
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main(!IO) :-
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promise_pure (
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( if solve_problem(Solution) then
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io.print("solution found: ", !IO),
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io.print(Solution, !IO),
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io.nl(!IO)
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else
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io.print("no solution found\n", !IO)
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)
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).
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:- pred solve_problem(int::out) is semidet.
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solve_problem(Solution) :-
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init(B),
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init(C),
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post_constraint( B \/ -C),
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post_constraint(-B \/ C),
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solve([B, C], Solution).
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:- solver type st
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where representation is int.
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:- pred init(st::oa) is det.
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init(A) :-
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promise_pure(impure A = 'representation to any st/0'(123)).
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:- func -(st::ia) = (st::oa) is det.
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-(A) = A.
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:- func (st::ia) \/ (st::ia) = (st::oa) is det.
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A \/ _ = A.
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:- pred post_constraint(st::ia) is semidet.
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post_constraint(_) :-
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semidet_succeed.
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:- pred solve(list(st)::ia, int::out) is semidet.
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solve(_, 42) :-
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semidet_succeed.
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