Adventures in Prolog - computations with lists IV

Today's post is merely a modification to yesterdays post, i.e. the remove duplicate functions will be streamlined. rem_dups2/2 is a replication of rem_dups/2 with less dependencies, i.e. it does not use the remove/3 predicate thereby improving performance. A drawback is that rem_dups2 does not preserve order of list elements when producing output, i.e. the last occurence of a duplicate list element will be preserved in the output list.

rem_dups2([X[]], [X]).

rem_dups2([HT], X) :-
member(H, T),
!,
rem_dups2(T, X);
rem_dups2(T, Y),
append([H], Y, X).