I've just published draft #4 of SRFI 151.  It was submitted by
John Cowan, author of the SRFI.

  <https://srfi.schemers.org/srfi-151/>

Here are John's comments on the draft:

  The changes here are in response to Will's comments.  We
  can announce last call.

Here's the diff:

  <https://github.com/scheme-requests-for-implementation/srfi-151/compare/7a3d41703f4fc2debd09c42bed98a9ca42be1ad9...5efcd6263841ce8c0f81cceb16bee3036c870db7>

Regards,

SRFI Editor