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Re: Updated issues list for SRFI 113

This page is part of the web mail archives of SRFI 113 from before July 7th, 2015. The new archives for SRFI 113 contain all messages, not just those from before July 7th, 2015.

Arthur A. Gleckler scripsit:

> Counting anything from a fixed set of possibilities, e.g. the number of
> each type of error in a log file or the number of uses of each word in a
> lexicon in a body of documents.  It's a special case of other data
> structures, e.g. hash tables mapping items to integers, but it's good to
> have because it clearly expresses the programmer's intent and can be
> optimized.  

I've merged this text into the SRFI.

> > If you add bags, a 'for-each-unique-element' procedure seems
> > essential - otherwise there seems to be absolutely no point.
> You're right.  There should also be a bag-unique-elements function, which
> returns the set of unique elements present in the particular bag.

Added as bag-for-each-unique and `bag->set` respectively.  I also added
`set->bag` for completeness, and resolved the issue about conversion.

> John, have you already done one of your comprehensive surveys of existing
> implementations?  I'd love to compare the proposal to what's already
> available.

There isn't much.  R6RS enumerations, Racket sets, and three Chicken
eggs: `sets`, `cis`, and `iset`.  Links are in the proposal, except
for `sets`, where there is no documentation: its module exports are
(make-empty-set set-copy set->list list->set set-add! set-remove! set-size
set-for-each set-has-member? set-is-subset? set-union! set-union
set-difference! set-difference set-intersection! set-intersection).

The new draft is at <http://ccil.org/~cowan/temp/srfi-113.html>.

Clear?  Huh!  Why a four-year-old child         John Cowan
could understand this report.  Run out          cowan@xxxxxxxx
and find me a four-year-old child.  I           http://www.ccil.org/~cowan
can't make head or tail out of it.
        --Rufus T. Firefly on government reports