I've just published draft #3 of SRFI 157.  It was submitted by Marc Nieper-Wißkirchen, author of the SRFI.

  <https://srfi.schemers.org/srfi-157/>

Here are Marc's comments on the draft:

  This should become a new draft (after, if any,

  editorial changes have been made).

  Depending on replies on the mailing list, that

  draft may go into "last call".

  Commit Summary

  - Minor fixes

  - Add optional default values (specification)

  - Add optional default values (implementation)

  - Add note on Racket compatibility

  - Add some implementation hints

  File Changes

  - M examples/fact.scm (13)

  - M examples/simple.scm (4)

  - M lib/inferior/expression.scm (14)

  - M lib/inferior/primitive.scm (61)

  - M lib/inferior/unspecified.scm (2)

  - M srfi-157.html (172)

Here's the diff:

  <https://github.com/scheme-requests-for-implementation/srfi-157/compare/04067fcefe1ca9d7bd2866b04a33a2c8a54196ed...6bf04bd3fd92597ed1949edbfeb223f20779967a>>

Regards,

SRFI Editor