% file: dict.p
%       version 1.03

% dictionary(Word, Pos, Listing).

dictionary(bluebird,noun,[[singular, bluebird], [plural, bluebirds]]).
dictionary(lily,noun,[[singular, lily], [plural, lilies]]).

dictionary(moose,noun,[[singular, moose], [plural, moose]]).
dictionary(goose,noun,[[singular, goose], [plural, geese]]).

dictionary(run,verb,[[singular, runs], [plural, run]]).
dictionary(fly,verb,[[singular, flies], [plural, fly]]).
dictionary(grow,verb,[[singular, grows], [plural, grow]]).
dictionary(do,verb,[[singular, does], [plural, do]]).

dictionary(this,det,[[singular, this], [plural, these]]).
dictionary(that,det,[[singular, that], [plural, those]]).
dictionary(the,det,[[singular, the], [plural, the]]).
dictionary(a,det,[[singular, a], [plural, the]]).

dictionary(high,adv,[[singular, high], [plural, high]]).
dictionary(fast,adv,[[singular, fast], [plural, fast]]).
dictionary(far,adv,[[singular, far], [plural, far]]).
dictionary(quickly,adv,[[singular, quickly], [plural, quickly]]).
dictionary(slowly,adv,[[singular, slowly], [plural, slowly]]).

pos(Word,Pos) :-
   dictionary(Word,Pos,_).

in_dict(Word) :-
   dictionary(Word,_,_).
in_dict(Word) :-
   in_dictionary(Word,_).

% in_dictionary(+Word, ?Entry)
in_dictionary(Word,Word) :-
   dictionary(Word,_,_).

in_dictionary(Word,Entry) :-
   singular_of(_,Word,Entry).

in_dictionary(Word,Entry) :-
   plural_of(_,Word,Entry).

% singular_of(Word,Singular,Entry) :: Word has singular Singular under
%                                              entry Entry
singular_of(Word,Singular,Word) :-
   dictionary(Word,_,Listing),
   extract(singular,Listing,Singular), !.

singular_of(Word,Singular,Entry) :-
   dictionary(Entry,_,Listing),
   in_listing(Word,Listing),
   extract(singular,Listing,Singular), !.

% plural_of(Word,Plural,Entry) :: Word has plural Plural under
%                                          entry Entry
plural_of(Word,Plural,Word) :-
   dictionary(Word,_,Listing),
   extract(plural,Listing,Plural), !.

plural_of(Word,Plural,Entry) :-
   dictionary(Entry,_,Listing),
   in_listing(Word,Listing),
   extract(plural,Listing,Plural), !.

in_listing(Word,[[_, Word] | _]).
in_listing(Word,[_ | Rest]) :- in_listing(Word,Rest).

extract(Attribute,[[Attribute, Value] | _], Value).
extract(Attribute,[_ | Rest], Value) :- extract(Attribute,Rest,Value).