<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content="text/html; charset=us-ascii" http-equiv=Content-Type> <META name=GENERATOR content="MSHTML 9.00.8112.16437"></HEAD> <BODY> <DIV dir=ltr align=left><SPAN class=359212520-14102011><FONT color=#0000ff size=2 face=Arial>In addition to my previous mail:put the code in the definitions window of DrRacket and use the macro stepper to see how the code is expanded.</FONT></SPAN></DIV> <DIV dir=ltr align=left><SPAN class=359212520-14102011><FONT color=#0000ff size=2 face=Arial>Jos</FONT></SPAN></DIV><BR> <DIV dir=ltr lang=en-us class=OutlookMessageHeader align=left> <HR tabIndex=-1> <FONT size=2 face=Tahoma><B>From:</B> users-bounces@racket-lang.org [mailto:users-bounces@racket-lang.org] <B>On Behalf Of </B>nicolas.oury@gmail.com<BR><B>Sent:</B> viernes, 14 de octubre de 2011 21:40<BR><B>To:</B> users@racket-lang.org<BR><B>Subject:</B> [racket] begin and let/cc<BR></FONT><BR></DIV> <DIV></DIV> <DIV>Dear all,</DIV> <DIV><BR></DIV> <DIV>I don't understand this behaviour:</DIV> <DIV><BR></DIV> <DIV>> (define k #f)</DIV> <DIV>> (begin (let/cc out (set! k out)) 5)</DIV> <DIV>5</DIV> <DIV>> (k #f)</DIV> <DIV>#f</DIV> <DIV>> (let () (let/cc out (set! k out)) 5)</DIV> <DIV>5</DIV> <DIV>> (k #f)</DIV> <DIV>5</DIV> <DIV><BR></DIV> <DIV><BR></DIV> <DIV>Does begin something special regarding continuation?</DIV> <DIV><BR></DIV> <DIV><BR></DIV> <DIV>Best regards,</DIV> <DIV><BR></DIV> <DIV>Nicolas.</DIV></BODY></HTML>