Scheme Request for Implementation 157,
"Continuation marks,"
by Marc Nieper-Wißkirchen,
is now available for discussion.

Its draft and an archive of the ongoing discussion are
available at <https://srfi.schemers.org/srfi-157/>.

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-157@srfi.schemers.org>.

Here's the abstract:

  Continuation marks are a programming language feature that
  allows one to attach information to and retrieve
  information from continuations, generalizing stack
  inspection.  Conceptually, a continuation consists of a
  number of frames where each frame stands for an active
  procedure call that is not a tail call.  At most one mark
  for a given key can be attached to a single frame.

  Besides stack inspection, continuation marks can be used
  to implement dynamic scope, delimited continuations, or
  delayed evaluation that is able to handle iterative lazy
  algorithms.

  This SRFI proposes to add continuation marks to the Scheme
  programming language.

Regards,

SRFI Editor