Scheme Request for Implementation 153,
"Ordered Sets,"
by John Cowan,
has gone into "withdrawn" status.

The document and an archive of the discussion are available at
<https://srfi.schemers.org/srfi-153/>.

Here's what John said about his decision to withdraw this SRFI:

  I've decided to stop working on SRFI 153.  I've updated the SRFI
  document, which is attached, and I'm also sending you a partial
  (and
  probably buggy) implementation of it.  I just don't care about
  working on it any more; I'd rather spend my Scheme time on SRFI
  160
  and future SRFIs.  Unless someone takes it over for a future
  edition, R7RS-large won't have ordered sets.

I've published the implementation John provided and his latest
version of the document, too.

I would like to thank John for his work on this SRFI.  Thanks,
too, to everyone who participated in the discussion of this SRFI.

It would be great if someone else decided to pick up where John
left off.  Having a good ordered sets API and implementation would
be a useful addition to Scheme's library of data structures.
Please contact me if you are interested — or just send me a new
SRFI!

Regards,

SRFI Editor