Re: [Tzdist-bis] Last Call: <draft-murchison-tzdist-tzif-13.txt> (The Time Zone Information Format (TZif)) to Proposed Standard

It's a fairly standard interval or range notation in mathematics that the
types of the brackets used are important.  I would imagine this appears in
plenty of other RFCs and the like.

The square left bracket next to 0 means "starting at and including 0",
while the round right bracket next to 'typecnt' means "up to but NOT
including 'typecnt'."  So there are a total of 'typecnt' elements, indexed
from 0 to 'typecnt'-1, inclusive.  Likewise for (desig)idx and charcnt.

https://en.wikipedia.org/wiki/Interval_(mathematics)

This convention of including the lower bound and excluding the upper has an
established history in computing as well:
https://www.cs.utexas.edu/users/EWD/transcriptions/EWD08xx/EWD831.html

--
Tim Parenti

On Thu, 13 Sep 2018 at 07:55, tom petch <daedulus@btconnect.com> wrote:

> My arithmetic may be letting me down, but in s.3.2, when there are
> 'typecnt' entries in a list of transition types, then I would expect the
> index to be
> [0, 'typecnt'-1)
> or
> [1, 'typecnt')
> but not
> [0, 'typecnt')
> as the I-D says, unless zero has a special meaning but then it is not
> really an index.
>
> Ditto for (desig)idx  and charcnt except that this list is NUL
> terminated, but then I would not expect it to be valid to index the NUL.
>
> I infer, and would rather be told explicitly, that
> "The total number of octets is specified by the 'charcnt' field ..
> excludes the NUL that terminates the list.
>
> In s.1,
> "the source the time zone data  metadata, identifiers, ..."
> would appear to be light of an 'of'.
>
> Tom Petch
>
> ----- Original Message -----
> From: "The IESG" <iesg-secretary@ietf.org>
> Cc: <lear@ofcourseimright.com>; <tzdist-bis@ietf.org>;
> <draft-murchison-tzdist-tzif@ietf.org>; <alexey.melnikov@isode.com>
> Sent: Tuesday, September 11, 2018 4:55 PM
>
> > The IESG has received a request from an individual submitter to
> consider the
> > following document: - 'The Time Zone Information Format (TZif)'
> >   <draft-murchison-tzdist-tzif-13.txt> as Proposed Standard
> >
> > The IESG plans to make a decision in the next few weeks, and solicits
> final
> > comments on this action. Please send substantive comments to the
> > ietf@ietf.org mailing lists by 2018-10-09. Exceptionally, comments may
> be
> > sent to iesg@ietf.org instead. In either case, please retain the
> beginning of
> > the Subject line to allow automated sorting.
> >
> > Abstract
> >
> >    This document defines the Time Zone Information Format (TZif) for
> >    representing and exchanging time zone information, independent of
> any
> >    particular service or protocol.  Two MIME media types for this
> format
> >    are also defined.
> >
> > The file can be obtained via
> > https://datatracker.ietf.org/doc/draft-murchison-tzdist-tzif/
> >
> > IESG discussion can be tracked via
> > https://datatracker.ietf.org/doc/draft-murchison-tzdist-tzif/ballot/
> >
> > No IPR declarations have been submitted directly on this I-D.
> >
>
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