builtins.pl

   1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2 % Author:       Tom Schrijvers
   3 % Email:        Tom.Schrijvers@cs.kuleuven.ac.be
   4 % Copyright:    K.U.Leuven 2004
   5 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   6 :- module(builtins,
   7         [
   8                 negate_b/2,
   9                 entails_b/2,
  10                 binds_b/2
  11         ]).
  12
  13 :- use_module(hprolog).
  14
  15 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  16 negate_b(true,fail).
  17 negate_b(fail,true).
  18 negate_b(X =< Y, Y < X).
  19 negate_b(X > Y, Y >= X).
  20 negate_b(X >= Y, Y > X).
  21 negate_b(X < Y, Y =< X).
  22 negate_b(var(X),nonvar(X)).
  23 negate_b(nonvar(X),var(X)).
  24
  25 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  26 entails_b(A,B) :-
  27         ( var(B) ->
  28                 entails(A,B,[A])
  29         ;
  30                 once((
  31                         entails(A,C,[A]),
  32                         B == C
  33                 ))
  34         ).
  35
  36 entails(A,A,_).
  37 entails(A,C,History) :-
  38         entails_(A,B),
  39         \+ hprolog:memberchk_eq(B,History),
  40         entails(B,C,[B|History]).
  41
  42 entails_(X > Y, X >= Y).
  43 entails_(X > Y, Y < X).
  44 entails_(X >= Y, Y =< X).
  45 entails_(X < Y, Y > X).
  46 entails_(X < Y, X =< Y).
  47 entails_(X > Y, X \== Y).
  48 entails_(X \== Y, Y \== X).
  49 entails_(X == Y, Y == X).
  50 entails_(ground(X),nonvar(X)).
  51 entails_(compound(X),nonvar(X)).
  52 entails_(atomic(X),nonvar(X)).
  53 entails_(number(X),nonvar(X)).
  54 entails_(atom(X),nonvar(X)).
  55 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  56 binds_b(G,Vars) :-
  57         binds_(G,L,[]),
  58         sort(L,Vars).
  59
  60 binds_(var(_),L,L).
  61 binds_(nonvar(_),L,L).
  62 binds_(ground(_),L,L).
  63 binds_(compound(_),L,L).
  64 binds_(number(_),L,L).
  65 binds_(atom(_),L,L).
  66 binds_(atomic(_),L,L).
  67 binds_(integer(_),L,L).
  68 binds_(float(_),L,L).
  69
  70 binds_(_ > _ ,L,L).
  71 binds_(_ < _ ,L,L).
  72 binds_(_ =< _,L,L).
  73 binds_(_ >= _,L,L).
  74 binds_(_ =:= _,L,L).
  75 binds_(_ =\= _,L,L).
  76 binds_(_ == _,L,L).
  77 binds_(_ \== _,L,L).
  78
  79 binds_(X is _,[X|L],L).
  80 binds_((G1,G2),L,T) :-
  81         binds_(G1,L,R),
  82         binds_(G2,R,T).
  83 binds_((G1;G2),L,T) :-
  84         binds_(G1,L,R),
  85         binds_(G2,R,T).
  86 binds_((G1->G2),L,T) :-
  87         binds_(G1,L,R),
  88         binds_(G2,R,T).
  89
  90 binds_(\+ G,L,T) :-
  91         binds_(G,L,T).