
The Japanese Calendar’s Y2K Moment - beefhash
https://blogs.msdn.microsoft.com/shawnste/2018/04/12/the-japanese-calendars-y2k-moment/
======
euske
As a taxpayer in Japan, I want the government to stop worrying about this
inefficient calendar system and fully adopt the Western calendar everywhere.

That said, I read the people's justifications are similar to those who favor
the Fahrenheit system in the US. They say the scale is close to their everyday
feel (under the current system, each era is roughly equivalent to one's
lifespan) than 4-digit numbers, and therefore more "human". Their emotional
attachment defies rationality.

~~~
tjpnz
You can fight back by cramming two extra digits into any paper form demanding
you express years in this manner.

~~~
contingencies
[https://en.wikipedia.org/wiki/ISO_8601](https://en.wikipedia.org/wiki/ISO_8601)
is elegant because it solves the US/UK date ordering conflict and
simultaneously renormalizes for most-to-least significant (which has been
standard in the Far East for thousands of years). Depoliticizing time is a
good thing(TM). See also: use of BCE suffix in dates:
[https://en.wikipedia.org/wiki/Common_Era](https://en.wikipedia.org/wiki/Common_Era)
and the total mess that is attempting to express to a human the actual meaning
of an entry in the TZ database. [http://tz.iana.narkive.com/QuK9m7tT/tz-
proposal-for-a-modern...](http://tz.iana.narkive.com/QuK9m7tT/tz-proposal-for-
a-modern-collapsed-namespace)

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nandemo
Two things that are missing from the article:

1) because of this problem, the government is considering keeping Heisei for a
while after the emperor steps down
[https://minhan.jp/4599](https://minhan.jp/4599) (in Japanese)

2) the Japanese calendar (specifically the year) is used in some official
documents and formalities, but in daily life people mostly use the Gregorian
calendar. If you ask a bunch of Japanese people what Heisei year is now, I bet
a significant percentage of them won't remember. I've worked as a software
engineer in Japan for over 10 years and I've never had to deal with Japanese
calendar years.

~~~
glandium
The Japanese driving license expose people to the Japanese calendar years, and
they are renewed every 3 or 5 years. Mine expires in 平31. So technically, it
might even expire in year 1 of the new era (it expires in July).

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testplzignore
So what happens if an emperor dies unexpectedly? Does all Japanese calendar
aware software break?

~~~
Iv
The Heisei era started in 1989 with the death of Hirohito (posthumously named
Showa). Since then, there was no unexpected death of emperors. Modern software
has never been put to the test.

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CoreDumpling
Taiwan had a similar problem just a few years ago:
[https://en.wikipedia.org/wiki/Y1C_Problem](https://en.wikipedia.org/wiki/Y1C_Problem)

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treve
Did they mess up character encoding, or are there really a bunch of question
marks in the registry.

~~~
andremat
From the article:

> The last value "2019 05 01" contains the temporary information
> "？？_？_??????_?"

~~~
IvyMike
Now I'm not sure if the thing contains a bunch of question marks (in two
different fonts, no less) or if somewhere (the original poster, the blog, your
OS, hacker news, my browser, my OS) the character encoding got dorked up.

For reference, here's what I see:
[https://imgur.com/a/VdcaQ0r](https://imgur.com/a/VdcaQ0r)

The fact that there are unicode "Fullwidth Question Mark"s as well as what
appear to be normal question marks make me thing there still is an encoding
issue.

~~~
JdeBP
As possibly should the fact that the Klingon in the title is greeked in the
header. (-:

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Iv
Honestly at this point if you are not storing dates in UTC form and
transforming it in order to get to the Japanese calendar format, you are doing
things wrong. The emperor is not eternal (yeah, I know, blasphemy) and the end
of the era is totally expected.

~~~
KMag
What does it mean to store a date in a time zone (such as UTC) form? Do you
mean store dates as timestamps of UTC midnight on that date? Even this isn't a
storage format: do you mean a big-endian Java epoch milliseconds timestamp,
ISO 8601 text, or some other format?

I think you mean they should be using some representation of a Gregorian
calendar date, be it text or binary.

In any case, it sounds like they should probably have something analogous to
the timezone database for converting between various calendars where the
mapping can't be determined in advance.

That brings up a good question: in the Islamic calendar, the new year doesn't
start until reception of a reliable lunar observation by a Muslim. How do they
get around this in strict Muslim countries? Do they have a second concept for
"year" that's identical to the year except in the observational requirement
and therefore can be treated the same, but because of name doesn't break the
religious law? I presume they don't go through the trouble of creating a low-
latency network to distribute the start-of-year signal and make timestamp-to-
string routines block near the year rollover until they've seen the signal.

~~~
Iv
Well look at how DST regulation changes (about one worldwide every six months)
are handled: tzdata is the most underrated project around. I would not be
surprised if islami calendars relied on something similar. In their case it is
easier as there are (to my knowledge) not several islamic zones observing
different rules.

[https://en.wikipedia.org/wiki/Tz_database](https://en.wikipedia.org/wiki/Tz_database)

~~~
KMag
Yes, that's the Wikipedia link to the timezone database I mentioned.

But, latency is the issue. The year doesn't officially change until a Muslim
makes the necessary lunar observation on the first evening of the new year.
You can't pre-calculate a human observation, so to be in strict compliance,
you'd need an efficient way to rapidly distribute the observation.

I'm sure that in practice, pre-calculation is almost always used. My question
is how this is rationalized in more strict conservative Islamic countries, (or
less likely, how they avoid using pre-calculated start of the new year).

~~~
bloak
I would guess that the people tasked with observing the new moon have a sense
of responsibility and know on which day they are expected to observe it, so
they do the right thing. It's easy enough to avoid observing the new moon too
early: just don't look at the sunset on the day before. Making sure you do
observe the new moon on the right day is harder, but if you have several
observatories you can probably manage it without self-deception almost every
time.

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rosege
ok selfish question but I fly into Tokyo on 28 April - Does anyone expect any
disruptions around the 30th?

