Kevin Wortman scripsit:

> I guess I lean toward including the intern! procedures, even if they are
> redundant.

Fair enough.  Added.

That resolves all issues but two, which I'll address in other postings:
#15 comparators for sets, and #16 merger procedures.  Modulo those, I
think that the API is now appropriate as an API for immutable (persistent)
sets as well, omitting the ! operations of course.

Looking at ImmutableDataStructuresWortman, I see the following
additional procedures:  iset/merger, iset-min, iset-max, iset-between,
iset-range= and friends, iset-map/monotone, iset->ordered-list,
and ordered-list->iset.  There is also Riastradh's universal update
procedure, which should perhaps be added to this SRFI's sets as well;
I'll make that #17.

Should we have ibags?  What about integer-isets using patricia trees,
like Haskell's Data.IntSet?  Although persistent sets won't be in this
SRFI, it makes sense to me to discuss them here.

--
John Cowan  http://ccil.org/~cowan    xxxxxx@ccil.org
There are books that are at once excellent and boring.  Those that at
once leap to the mind are Thoreau's Walden, Emerson's Essays, George
Eliot's Adam Bede, and Landor's Dialogues.  --Somerset Maugham