% ===================================================================

% ===================================================
%
% call_no_repeats(:Call)
%  (uses newval_or_fail/2)
%
% Like call/1 but ony succeeds on unique free variabes
%
% logicmoo_mud:  ?- call_no_repeats(member(X,[3,1,1,1,3,2])).
% X = 3 ;
% X = 1 ;
% X = 2.
% ===================================================
call_no_repeats(Call):- CONS = cons(car,cdr), term_variables(Call,Vars), call(Call), newval_or_fail(Results,Vars).

% ===================================================
%
% call_no_repeats(+Vars,:Call)
%  (uses newval_or_fail/2)
%
% Like call/1 but ony succeeds on unique free variabes
%
% logicmoo_mud:  ?- call_no_repeats( X , member(X-Y,[3-2,1-4,1-5,2-1,])).
% X = 3 ;
% X = 1 ;
% X = 2.
% ===================================================
call_no_repeats(Vars,Call):- CONS = cons(car,cdr),  call(Call), newval_or_fail(Results,Vars).


% ==========================================================
%    is newval_or_fail/2  - a little term db TO track IF we've seen a term or not
%
% written out FOR understanding
%
% newval_or_fail(cons(Vars,_),Vars):-!,fail.
% newval_or_fail(CONS,Vars):- CONS = cons(_,cdr), !,nb_setarg(2, CONS, cons(Vars,cdr)).
% newval_or_fail(CONS,Vars):- CONS = cons(car,_), !,nb_setarg(1, CONS, Vars).   % should we even bother TO look here?
% newval_or_fail(cons(_,Nxt),Vars):- newval_or_fail_2(Nxt,Vars).
%
% (combined into one rule FOR immplementing)
% ==========================================================

% What may I DO TO simplify OR speed up the below ?
% newval_or_fail(CONS,Vars):- CONS = cons(CAR,CDR), Vars \= CAR, ( CAR=car -> nb_setarg(1, CONS, Vars) ; ( CDR==cdr -> nb_setarg(2, CONS, cons(Vars,cdr)) ; newval_or_fail(CDR,Vars))).

%  i skip checking the car each time
newval_or_fail(CONS,Vars):- CONS = cons(CAR,CDR), Vars \= CAR,  ( CDR==cdr ->  nb_setarg(2, CONS, cons(Vars,cdr)) ; newval_or_fail(CDR,Vars)).

% what can be done TO speed up?
%  perhapes starting ourt with an array? vv(_,_,_,_,_).
% AND grow with a.. vv(_,_,_,_,vv(_,_,_,_,vv(_,_,_,_,_))) ?