Unhelpful error message

[zkessin]

If you have a file like this example where there is not a trailing newline erlog will give you a compile time error about "Operator expected" when what it really wants is a \n at the end of the last line of code. We should make it ether just compile it without the \n or at least provide a more useful error message

%-*-prolog-*-

sum_to(1,1) :- !.
sum_to(N, Res) :-
    N1 is N - 1,
    sum_to(N1, Res1),
    Res is Res1 + N.

test(_File) :-
    sum_to(5,15).