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.
This convention of including the lower bound and excluding the upper has an established history in computing as well:
--
Tim Parenti
Tim Parenti
On Thu, 13 Sep 2018 at 07:55, tom petch <daedulus@xxxxxxxxxxxxx> 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@xxxxxxxx>
Cc: <lear@xxxxxxxxxxxxxxxxxxx>; <tzdist-bis@xxxxxxxx>;
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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
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> 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/
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> IESG discussion can be tracked via
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