void is a good placeholder in dummy functions/objects. It doesn't do anything, except for fill a gap, which is useful. Values is used to pass multiple values. Check the manual for details. Does that help? Stephen <div class="gmail_quote">On Sun, 23 Nov 2014 at 12:56 Roman Klochkov <<a href="mailto:kalimehtar@mail.ru">kalimehtar@mail.ru</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div>When I should use (void) and when (values)? They are both used to show, that there are no return values. They are both not printable. What is intended use for (void) and (values) and when one should prefer one over other? -- Roman Klochkov</div> ____________________ Racket Users list: <a href="http://lists.racket-lang.org/users" target="_blank">http://lists.racket-lang.org/users</a> </blockquote></div>