[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
master 523261b454 6/7: Document calc-time-zone abbreviation obsolescence
From: |
Paul Eggert |
Subject: |
master 523261b454 6/7: Document calc-time-zone abbreviation obsolescence |
Date: |
Fri, 30 Dec 2022 00:32:26 -0500 (EST) |
branch: master
commit 523261b454058d0b28df2c3de1eab55fe378aa69
Author: Paul Eggert <eggert@cs.ucla.edu>
Commit: Paul Eggert <eggert@cs.ucla.edu>
Document calc-time-zone abbreviation obsolescence
* doc/misc/calc.texi (Time Zones): Document that alphabetic
time zone abbreviations are obsolescent and in some cases wrong.
---
doc/misc/calc.texi | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/doc/misc/calc.texi b/doc/misc/calc.texi
index ef9990c057..e5bac25cac 100644
--- a/doc/misc/calc.texi
+++ b/doc/misc/calc.texi
@@ -17341,8 +17341,12 @@ it can be a variable which is a time zone name in
upper- or lower-case.
For example @samp{tzone(PST) = tzone(8)} and @samp{tzone(pdt) = tzone(7)}
(for Pacific standard and daylight saving times, respectively).
-North American and European time zone names are defined as follows;
-note that for each time zone there is one name for standard time,
+North American and European time zone names are defined as follows.
+These names are obsolescent and new code should not rely on them:
+the @samp{YST}-related names have disagreed with time in Yukon since 1973,
+and other names could well become confusing or wrong in the future
+as countries change their time zone rules.
+For each time zone there is one name for standard time,
another for daylight saving time, and a third for ``generalized'' time
in which the daylight saving adjustment is computed from context.
@@ -17364,7 +17368,7 @@ To define time zone names that do not appear in the
above table,
you must modify the Lisp variable @code{math-tzone-names}. This
is a list of lists describing the different time zone names; its
structure is best explained by an example. The three entries for
-Pacific Time look like this:
+circa-2022 US Pacific Time look like this:
@smallexample
@group
- master updated (91ae9f3d12 -> 9153cf8158), Paul Eggert, 2022/12/30
- master 523261b454 6/7: Document calc-time-zone abbreviation obsolescence,
Paul Eggert <=
- master 007e66bccb 5/7: Use RFC 822 abbrevs in sunrise-sunset strings, Paul Eggert, 2022/12/30
- master 8c13e84978 1/7: Fix newsticker timezone decode, Paul Eggert, 2022/12/30
- master 73769dc2b8 2/7: In cal-dst, be consistent re default to UTC, Paul Eggert, 2022/12/30
- master bc4cbbcc57 4/7: Add nndiary-headers obsolescence comment, Paul Eggert, 2022/12/30
- master d11e34ce76 3/7: Default mbox "From " time zone to -0000, Paul Eggert, 2022/12/30
- master 9153cf8158 7/7: Avoid some obsolescent tz abbrevs in doc., Paul Eggert, 2022/12/30