/* not needed in 3.8.5
catch( Goal, Catcher, Recovery ) :-
	on_exception(Catcher, Goal, Recovery).

throw(Ball) :-
	raise_exception(Ball).

atom_codes( Atom, Codes ) :-
	atom_chars( Atom, Codes ).

*/

% simulate swi's predicate.
% unfortunately a return is required.

get_single_char( C ) :-
	get0( C ).

get_line( Cs ) :-
	( at_end_of_line -> 
		get0( _EndOfLine ),
		Cs = []
		;
		get0( Cprime ),
		Cs = [Cprime|Tcs],
		get_line( Tcs )
	).