Scheme Request for Implementation 154,
"First-class dynamic extents,"
by Marc Nieper-Wißkirchen,
has gone into "final" status.

The document and an archive of the discussion are available at
<https://srfi.schemers.org/srfi-154/>.

Here's the abstract:

  Scheme has the notion of the dynamic extent of a procedure call.
  A number of standard Scheme procedures and syntaxes like
  dynamic-wind, call-with-current-continuation, and parameterize
  deal with the dynamic extent indirectly.  The same holds true
  for the procedures and syntaxes dealing with continuation marks
  as defined by SRFI 157.

  This SRFI reifies the dynamic extent into a first-class value
  together with a well-defined procedural interface and a syntax
  to create procedures that remember not only their environment at
  creation time but also their dynamic extent, which includes
  their dynamic environment.

Many thanks to the author and to everyone who contributed to the
discussion of this SRFI.

Regards,

SRFI Editor