[racket] Reading Graph Structure: read: #..= expressions not allowed in read-syntax mode (??)

From: Eli Barzilay (eli at barzilay.org)
Date: Mon Jun 6 09:14:06 EDT 2011

20 minutes ago, Marijn wrote:
> Hash: SHA1
> Hi,
> why does the following code
> #lang racket
> (struct _dl (left val right))
> (define (dlist a b c)
>   #1=(_dl #f a #2=(_dl #1# b (_dl #2# c #f))) )

Note that you wrote an infinite piece of code there, which very few
implementations would allow you to do.  (It used to be a cute trick in
the distant past.)  I've tried a few implementations, and they fail in
a much less graceful way: some schemes just got stuck in an infinite
loop, and some lisps threw a stack overflow error.

          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!

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