[tz] [PATCH 00/10] Zone Table Comments

J William Piggott elseifthen at gmx.com
Wed Mar 2 01:58:13 UTC 2016

On 03/01/2016 02:04 AM, Paul Eggert wrote:
>Brian Inglis wrote:
>> Not clear in lines such as those below that Eastern, Central refer to time zone
>> and not the geographical part of the region - either add the word Time or some
>> other indication e.g. EST/EDT, CST/CDT to keep it short:
>In context it's not so bad (see below for the relevant screen, for
>Canada). Perhaps "EST+EDT" would be clearer than "Eastern" and similarly
>for "CST+CDT" and I suppose "MST+MDT" and "PST+PDT" but it's a close
>Please select one of the following time zone regions.
> 1) Newfoundland; Labrador (southeast)    15) Central - NU (Resolute)
> 2) Atlantic - NS (most areas); PE    16) Central - NU (central)
> 3) Atlantic - NS (Cape Breton)        17) CST - SK (most areas)
> 4) Atlantic - New Brunswick        18) CST - SK (midwest)
> 5) Atlantic - Labrador (most areas)    19) Mountain - AB; BC (E); SK (W)
> 6) AST - QC (Lower North Shore)    20) Mountain - NU (west)
> 7) Eastern - ON, QC (most areas)    21) Mountain - NT (central)
> 8) Eastern - ON, QC (no DST 1967-73)    22) Mountain - NT (west)
> 9) Eastern - ON (Thunder Bay)        23) MST - BC (Creston)
>10) Eastern - NU (most east areas)    24) MST - BC (Dawson Cr, Ft St John)
>11) Eastern - NU (Pangnirtung)        25) MST - BC (Ft Nelson)
>12) EST - ON (Atikokan); NU (Coral H)    26) Pacific - BC (most areas)
>13) Central - ON (west); Manitoba    27) Pacific - Yukon (south)
>14) Central - ON (Rainy R, Ft Frances)    28) Pacific - Yukon (north)

When I was considering how to shorten US and CA enough so they
would page correctly, the most obvious target was the common
zone name prefix.  In light of the recent discussion on the
mailing list with regard to dropping alpha zone abbreviations
in favor of offsets, I was going to try a patch to replace the
existing comments' prefix with offsets. I thought this might
be accepted, because it is already used for RU. I was going to
take it a step further by applying a simple offset as done
with "+02 - Central Africa Time" as a prefix to all of the
zone table comments. Is DST information needed to choose a
zone file? In the example list above it doesn't seem to be.

On a related subject; I saw when you where shorting the zone
table comments, Paul, that you also noticed the ordering was
not so good and jockeyed that around as well. That is the
reason I submitted a patch to sort the local regions' lists.
If all of the comments were prefixed with an offset, then
sorting the tzselect menus would create the geographical
ordering to which you gave priority over a lexical sort. This
would make maintaining the zone tables easier, because strict
attention to order within the file would no longer matter. The
fact that you just had to rearranged the file order illustrates
how this collation creep can work its way in over time.

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