5 ms·

> because how hard can it be to work with dates? Oh man, tell me about it. Timezones are the worst. No wonder so many people just give up and use Moment.js.

dheera 5y ago
Use UTC UNIX timestamps (i.e. Date.now()) for ALL time-related processing and only convert to hours/minutes when taking input/output from the user.
- aidos 5y ago
  Uh oh, we’re going there again. If you’re doing anything in the future, that’s not always the correct thing to do. (Instants vs wall time etc)
- mypalmike 5y ago
  That's a good starting point, and certainly good advice for marking current time and past times. But keep in mind that future event absolute UTC can change due to politics, e.g. a change in daylight savings rules, which is less rare than you might imagine (https://en.m.wikipedia.org/wiki/Daylight_saving_time_by_country#Past_observance https://en.m.wikipedia.org/wiki/Daylight_saving_time_by_coun...). That concert scheduled a year from now at 8pm in UTC+5 might actually end up occurring at 8pm in UTC+6.
  - notreallyserio 5y ago
    > certainly good advice for marking current time and past times But not too far past!
- anchpop 5y ago
  Hmm, I think you should use TAI over UTC because UTC has leap-second corrections, Which means that the current time + X seconds might not actually be X seconds from now
- misnome 5y ago
  But I want my 4pm weekly meeting to always happen at 4pm, even if DST changes.
  - dheera 5y ago
    If DST changes and you live in a democracy, it's your fault. Vote against DST. If you don't get what you want unleash the wrath on your congress member, not the software.
- amalcon 5y ago
  I once had briefly traveled into a different time zone (so briefly that I hadn't thought about it) when I received a phone call asking to reschedule a doctor appointment. I entered the new time into my calendar. Then, I was an hour late to the appointment. My phone had adopted the timezone of the cell tower, and the calendar assumed I had meant "local time where I scheduled the appointment".
jwandborg 5y ago
I've been bit by bugs when coming to moment.js from other languages. It's the only datetime library I knew of, before you'll tell me about all the others, that mutates the datetime object when you do arithmetic.

dheera 5y ago

Use UTC UNIX timestamps (i.e. Date.now()) for ALL time-related processing and only convert to hours/minutes when taking input/output from the user.

aidos 5y ago
Uh oh, we’re going there again. If you’re doing anything in the future, that’s not always the correct thing to do. (Instants vs wall time etc)
mypalmike 5y ago
That's a good starting point, and certainly good advice for marking current time and past times. But keep in mind that future event absolute UTC can change due to politics, e.g. a change in daylight savings rules, which is less rare than you might imagine (https://en.m.wikipedia.org/wiki/Daylight_saving_time_by_country#Past_observance https://en.m.wikipedia.org/wiki/Daylight_saving_time_by_coun...). That concert scheduled a year from now at 8pm in UTC+5 might actually end up occurring at 8pm in UTC+6.
- notreallyserio 5y ago
  > certainly good advice for marking current time and past times But not too far past!
anchpop 5y ago
Hmm, I think you should use TAI over UTC because UTC has leap-second corrections, Which means that the current time + X seconds might not actually be X seconds from now
misnome 5y ago
But I want my 4pm weekly meeting to always happen at 4pm, even if DST changes.
- dheera 5y ago
  If DST changes and you live in a democracy, it's your fault. Vote against DST. If you don't get what you want unleash the wrath on your congress member, not the software.
amalcon 5y ago
I once had briefly traveled into a different time zone (so briefly that I hadn't thought about it) when I received a phone call asking to reschedule a doctor appointment. I entered the new time into my calendar. Then, I was an hour late to the appointment. My phone had adopted the timezone of the cell tower, and the calendar assumed I had meant "local time where I scheduled the appointment".

jwandborg 5y ago

I've been bit by bugs when coming to moment.js from other languages. It's the only datetime library I knew of, before you'll tell me about all the others, that mutates the datetime object when you do arithmetic.