[plt-scheme] Help with #0 and #0# notation in the REPL

From: John Clements (clements at brinckerhoff.org)
Date: Tue Jan 29 20:08:08 EST 2008

On Jan 29, 2008, at 4:44 PM, Paul Schlie wrote:

> "It only ever worked for quoted cyclic data (and that's what's gone  
> now)."
> (sarcasm on) by what logic was this determined? personally I've used  
> cyclic
> data to describe many things, inclusive of syntax, semantic, and state
> transition information, and can see no obvious benefit to having to
> construct such information programmatically, not to mention that  
> once it
> was so constructed, it can't be easily written to a file, and then
> correspondingly easily restored via read with out such a  
> capability); of
> course with immutable lists, programmatic construction, isn't the  
> easiest
> either, so might as well eliminate any vestiges of enabling lists as  
> the
> basis of a flexible variable data structure. As after all, scheme  
> wasn't
> ever known to be a powerful friendly flexible programming language  
> (sarcasms
> off).

Hang on... to the best of my knowledge, (shared ...) allows you to  
define circular data without multi-step programmatic construction, and  
read/write _do_ support writing and reading of cyclic data.  No?

BTW, it's hard to understand you with sarcasm on.  I would leave it off.

All the best,


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