I've just published draft #7 of SRFI 152.  It was submitted
by John Cowan, author of the SRFI.

  <https://srfi.schemers.org/srfi-152/>

Here are John's comments on the draft:

  The main change from the previous last call is the removal
  of the optional procedures.  While the procedures
  themselves are relevant to the theme of the SRFI,
  R7RS-small does not have satisfactory support for making
  parts of an interface optional, because there is no
  portable way for a module to extend the set of features.
  The casing, UTF conversion, and normalization procedures
  by themselves don't make a coherent SRFI, especially given
  that R7RS-small supports casing and UTF-8 conversion
  already, so the whole matter will be left to some possible
  future Unicode SRFI.

  In addition, I've made all of Sven Hartrumpf's minor
  changes, and extended the rationale for
  `string-concatenate-reverse` as follows:

  # This procedure is useful when constructing procedures
  # that accumulate character data into lists of string
  # buffers, and wish to convert the accumulated data into a
  # single string when done.  The optional <var>end</var>
  # argument accommodates that use case by allowing the
  # final buffer to be only partially full without having to
  # copy it a second time, as <code>string-take</code> would
  # require.

  Shiro Kawai requested the removal of the reference to
  buffers, which I have done.

Here's the diff:

  <https://github.com/scheme-requests-for-implementation/srfi-152/compare/8ecd5acd9bf083142b4d3fe29287012287fb0793...3f0dcafebc8909e8c2a18922fa274326be494845>

Regards,

SRFI Editor