> On Nov 28, 2018, at 07:15, Matthew Flatt <mfl...@cs.utah.edu> wrote:
> Yes, that's special handling for pairs in the sense that the
> traditional Racket implementation takes advantage of leftover bits in a
> pair object, and it uses two of them for "is a list" and "not a list".
> Racket-on-Chez doesn't have the extra bits to work with, so "is a list"
> and "not a list" information is recorded separately in an `eq?`-based
> hash table.

Why does keeping track of “is a list” and “not a list” require two bits? It 
seems like a pair either is or is not a list, so one bit of information would 
be sufficient. Are there situations where the system can neither be sure that 
something is or is not a list? Circular lists, or something like that?

(This is not really important, of course, I’m just curious.)


You received this message because you are subscribed to the Google Groups 
"Racket Users" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to racket-users+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to