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