SRFI 158: Generators and Accumulators Arthur A. Gleckler 13 Aug 2017 07:38 UTC
Scheme Request for Implementation 158,
"Generators and Accumulators,"
by Shiro Kawai, John Cowan, and Thomas Gilray,
is now available for discussion.
Its draft and an archive of the ongoing discussion are
available at <https://srfi.schemers.org/srfi-158/>.
You can join the discussion of the draft by filling out the
subscription form on that page.
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John Cowan added this note about the new SRFI:
SRFI 158 will obsolete SRFI 121 when it is finalized. A
few new generator procedures have been added, and a new
concept of accumulators (the dual of generators) along
with some possibly-useful accumulator constructors.
Here's the abstract:
This SRFI defines utility procedures that create,
transform, and consume generators. A generator is simply
a procedure with no arguments that works as a source of
values. Every time it is called, it yields a value.
Generators may be finite or infinite; a finite generator
returns an end-of-file object to indicate that it is
exhausted. For example, read-char, read-line, and read
are generators that generate characters, lines, and
objects from the current input port. Generators provide
This SRFI also defines procedures that return
accumulators. An accumulator is the inverse of a
generator: it is a procedure of one argument that works as
a sink of values.