:- ensure_loaded( library(system) ). :- ensure_loaded( library(lists) ). :- ensure_loaded( library(debug) ). % :- debug(say). say(InArgs) :- ( is_list(InArgs) -> Args = InArgs; Args = [InArgs] ), debug( say, 'Args: ~w', [Args] ), write_args( Args ). write_args( [] ). write_args( [H|T] ) :- write( H ), nl, write_args( T ).