<html> <head> <style></style> </head> <body class='hmmessage'><div dir='ltr'> Matthias wrote: > That is indeed a strange thing considering that set-cdr! is no longer a part of the language :-) Yes indeed a very strange thing :-) > In these areas, read-syntax takes over. Enter > > (read) > > at the prompt. Type > > #0=(1 . #0#) > > into the input box that appears. > I've done that and what displays is: #0=(1  . #0#) #0='(1 . #0#) Again I'm not clear why this doesn't try to produce an endlessly recurring (1 . (1 . ( 1 .......  list Thanks, Harry Spier <div>> Subject: Re: [racket] Reading graph structure > From: matthias@ccs.neu.edu > Date: Thu, 18 Aug 2011 09:25:06 -0400 > CC: users@racket-lang.org > To: harryspier@hotmail.com > > > On Aug 18, 2011, at 9:09 AM, Harry Spier wrote: > > > When I put (#1=100 #1# #1#) in either the definitions or interactions window I get > > > > . read: #..= expressions not allowed in read-syntax mode > > > In these areas, read-syntax takes over. Enter > > (read) > > at the prompt. Type > > #0=(1 . #0#) > > into the input box that appears. > > > > > Also I'm not clear how #0=(1 . #0#) converts to > > (let ([v (cons 1 #f)]) > > (set-cdr! v v) v) > > > That is indeed a strange thing considering that set-cdr! is no longer a part of the language :-) > > > -- Matthias > > </div> </div></body> </html>