pairlist.pl

   1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2 %%              _      _ _     _
   3 %%  _ __   __ _(_)_ __| (_)___| |_
   4 %% | '_ \ / _` | | '__| | / __| __|
   5 %% | |_) | (_| | | |  | | \__ \ |_
   6 %% | .__/ \__,_|_|_|  |_|_|___/\__|
   7 %% |_|
   8 %%
   9 %% * author: Tom Schrijvers
  10
  11 :- module(pairlist,[
  12                 fst_of_pairs/2,
  13                 lookup/3,
  14                 lookup_any/3,
  15                 lookup_eq/3,
  16                 lookup_any_eq/3,
  17                 pairup/3,
  18                 snd_of_pairs/2,
  19                 translate/3
  20         ]).
  21
  22 fst_of_pairs([],[]).
  23 fst_of_pairs([X-_|XYs],[X|Xs]) :-
  24         fst_of_pairs(XYs,Xs).
  25
  26 snd_of_pairs([],[]).
  27 snd_of_pairs([_-Y|XYs],[Y|Ys]) :-
  28         snd_of_pairs(XYs,Ys).
  29
  30 pairup([],[],[]).
  31 pairup([X|Xs],[Y|Ys],[X-Y|XYs]) :-
  32         pairup(Xs,Ys,XYs).
  33
  34 lookup([K - V | KVs],Key,Value) :-
  35         ( K = Key ->
  36                 V = Value
  37         ;
  38                 lookup(KVs,Key,Value)
  39         ).
  40
  41 lookup_any([K - V | KVs],Key,Value) :-
  42         (
  43                 K = Key,
  44                 V = Value
  45         ;
  46                 lookup_any(KVs,Key,Value)
  47         ).
  48
  49 lookup_eq([K - V | KVs],Key,Value) :-
  50         ( K == Key ->
  51                 V = Value
  52         ;
  53                 lookup_eq(KVs,Key,Value)
  54         ).
  55
  56 lookup_any_eq([K - V | KVs],Key,Value) :-
  57         (
  58                 K == Key,
  59                 V = Value
  60         ;
  61                 lookup_any_eq(KVs,Key,Value)
  62         ).
  63
  64 translate([],_,[]).
  65 translate([X|Xs],Dict,[Y|Ys]) :-
  66         lookup_eq(Dict,X,Y),
  67         translate(Xs,Dict,Ys).
  68
  69 delete([], _, []).
  70 delete([K - V| KVs], Key, PL) :-
  71         ( Key = K ->
  72                 PL = KVs
  73         ;
  74                 PL = [ K - V | T ],
  75                 delete(KVs, Key, T)
  76         ).
  77
  78 delete_all([], _, []).
  79 delete_all([K - V| KVs], Key, PL) :-
  80         ( Key = K ->
  81                 delete_all(KVs, Key, PL)
  82
  83         ;
  84                 PL = [ K - V | T ],
  85                 delete_all(KVs, Key, T)
  86         ).
  87
  88 delete_eq([], _, []).
  89 delete_eq([K - V| KVs], Key, PL) :-
  90         ( Key == K ->
  91                 PL = KVs
  92         ;
  93                 PL = [ K - V | T ],
  94                 delete_eq(KVs, Key, T)
  95         ).
  96
  97 delete_all_eq([], _, []).
  98 delete_all_eq([K - V| KVs], Key, PL) :-
  99         ( Key == K ->
 100                 delete_all_eq(KVs, Key, PL)
 101         ;
 102                 PL = [ K - V | T ],
 103                 delete_all_eq(KVs, Key, T)
 104         ).
 105