SWI-Prolog - show long list

Have a look at: http://www.swi-prolog.org/FAQ/AllOutput.html

The simple solution is to type w after the answer is given, i.e.:

?- n_queens_problem(10,X).
X = [1, 3, 6, 8, 10, 5, 9, 2, 4|...] [write]
X = [1, 3, 6, 8, 10, 5, 9, 2, 4, 7] 

After you have pressed the "w"-key "[write]" is displayed at the end and the full solution appears in the next line.


I've found two ways.


1.

?- set_prolog_flag(answer_write_options,[max_depth(0)]).
true.

Then do your command that is printing a truncated list.

(set_prolog_flag documentation)


2.

?- atom_chars(goodbye_prolog, X) ; true.

(AllOutput documentation)

Put ; true. at the end of the call that results in a long list. Then push the w key on your keyboard. The result is:

?- sudoku([_,_,2,3,_,_,_,_,_,_,_,_,3,4,_,_], Solution); true.
Solution = [4, 1, 2, 3, 2, 3, 4, 1, 1|...] [write]
Solution = [4, 1, 2, 3, 2, 3, 4, 1, 1, 2, 3, 4, 3, 4, 1, 2] ;
true.

If prolog returns only one answer, you can make it wait by typing "; true." after the predicate. Then, if you press "w", you will get to see the whole list as written in the doc : http://www.swi-prolog.org/FAQ/AllOutput.html