Scheme Request for Implementation 137,
"Minimal Unique Types,"
by John Cowan and Marc Nieper-Wißkirchen,
is now available for discussion.

Here are John's earlier comments about the SRFI:

  I've just put together UniqueTypesCowan, which is a very
  non-R6RS, non-SRFI-99 style of procedural records that has
  zero in common with any syntactic record system.  It's
  based on UniqueTypesSnellPym, an old proposal for WG1 that
  didn't get any legs.  It's ultra-simple, provides runtime
  disjoint types and subtypes and very little else, and
  exposes no ambient authority of any kind.

  I have shipped the proposed SRFI with a few editorial
  changes to the SRFI editor, with a pointer to your
  [Marc's] implementation.

Its draft and an archive of the ongoing discussion are
available at <http://srfi.schemers.org/srfi-137/>.

You can join the discussion of the draft by filling out the
subscription form on that page.

You can contribute a message to the discussion by sending it
to <srfi-137@srfi.schemers.org>.

Regards,

SRFI Editor