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% Last in list problem. Learns recursive clauses for last(Element,List)

:- modeh(*,last(+constant,+clist))?
:- modeb(1,+constant = #constant)?
:- modeb(1,+clist = [-constant|-clist])?
:- modeb(*,last(+constant,+clist))?

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% Types

clist([]).
clist([H|T]) :- constant(H), clist(T).

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% Positive examples

last(a,[a]).
last(b,[b]).
last(c,[c]).
last(a,[b,a]).
last(b,[a,b]).
last(c,[a,c]).
last(c,[b,c]).

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% Negative examples

:- last(X,[]).
:- last(X,[Y]), not(X==Y).
:- last(1,[1,2]).
:- last(a,[c,a,b]).
:- last(0,[1,2]).