In preparation for writing SRFI 133, a proposed replacement for SRFI
43 and possible component of R7RS-large, I'm publishing a summary and
the results of the poll I ran on this mailing list.  The issue I was
asking about was the conflict between SRFI 43 and R7RS-small versions
of vector-map and vector-for-each.  The The SRFI 43 versions pass the
index of the current vector elements as well as the elements themselves
to their procedure arguments, whereas the R7RS-small versions pass only
the elements.  These are called "index form" and "non-index form" below.

I proposed four options:

1) Live with the conflict, using the library system to resolve which
version of these procedures you want.

2) Write a new SRFI in which vector-map and vector-for-each are renamed to
vector-map/index and vector-for-each/index.  This resolves the conflict
but is inconsistent with the other procedures of SRFI 43 that are in
index form.

3) Write a new SRFI in which all the vector-* procedures that pass an
index, namely -fold -fold-right -map -map! -for-each, are split into
two procedures, an index form ending in "/index" and a non-index form
with no suffix.

4) Introduce a mechanism into Scheme to allow vector-map and
vector-for-each to determine if their procedure arguments expect to be
called in index form or not.

Shiro Kawa and Alex Shinn separately proposed:

5) Write a new SRFI in which the five procedures listed under 3 are
provided in non-index form in addition to vector-fold (but nothing
else) in index form under a new name.  (Alex proposed to call it
vector-tabulate, but SRFI 1 tabulate is a constructor, not a fold.)

Votes:

Sven Hartrumpf preferred 3.
Shiro Kawa preferred 5.
Taylor Campbell preferred 1 to 3 to 2.
Art Gleckler preferred 2 to 1 to 3 to 4.
Sudarshan Chawathe preferred 2 to 3 to 1 to 4.
Alex Shinn preferred 5 to 3 to 1.
Faré preferred 3 to 2.

--
John Cowan          http://www.ccil.org/~cowan        xxxxxx@ccil.org
Kill Gorgun!  Kill orc-folk!  No other words please Wild Men.  Drive away
bad air and darkness with bright iron!   --Ghan-buri-Ghan