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Never write your own date parsing library

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Re: Never write your own date parsing library

#141

Post by brianpan »

avanwyk wrote: post #139
quelsolaar wrote: post #100

When ever i see "never implement your own...", i know i want to implement it myself. People say that about hard things, and I only want to do hard things. Nobody wants people who can do easy things, people want people who can do hard things. The only way to learn how to do hard things, is to do hard things, so do the hardest things. So go ahead, write your own date library, your own Unicode font rendering, compiler,…

I can't believe this is such a controversial take. Solving hard things by yourself is growth. I 100% agree, rather solve a hard solved problem yourself than learning yet another JS framework or launching yet another revenue losing SaaS ("successful" because of VC). Or whatever. Push hard boundaries.

It's controversial because 1) good on someone for wanting to do something difficult and 2) I cannot think of a worse thing to try to implement. Maybe trying to parse the world's postal and street addresses is a close second?

Just, why.

Re: Never write your own date parsing library

#144

Post by benlivengood »

ceejayoz wrote: post #77
BurningFrog wrote: post #67

Earlier quoted context omitted.

A second is still originally defined as 1/86400 of an Earth day. That doesn't make it unusable as a cross galactic time unit, and I think the same goes for years and hours.

Seconds are now (in SI) defined as calculated from behavior of cesium-133 atoms. https://en.wikipedia.org/wiki/Caesium_standard

Unfortunately, the Second is measured for purposes of our timekeeping standards at sea-level on Earth which is ~1PPB slower than it would be in free space, as opposed to having a correction factor built into our time standards and so, for example, interplanetary ping times would be slightly shorter (in UTC/TIA nanoseconds) than expected.

Re: Never write your own date parsing library

#146

Post by senfiaj »

somat wrote: post #119
senfiaj wrote: post #40

In UIs prefer date/time pickers instead of raw text inputs which will give the date/time in standard ISO format such as ("2025-07-25" or "2025-07-25T18:47:26.022Z"). Prefer ISO formats everywhere where possible.

The thing that bothers me about the firefox date picker is it display the date in YYYY/DD/MM format. While I am fairly sure this a a locale defined thing. locales are this huge pile of worms and I have never figured out how to change it to show YYYY-MM-DD format

At least the real input value is in YYYY-MM-DD. Also the date picker will show the day in it's calendar UI.

Re: Never write your own date parsing library

#147

Post by slyall »

dmoy wrote: post #50
TheJoeMan wrote: post #35

Earlier quoted context omitted.

It's funny to reason why we must go to bed when the clock has a certain number, since modern technology could easily be programmed to adjust as needed. No technical reasons the Martians can't go to bed at 9:00am today and 9:40am tomorrow. This mirrors my thoughts on why farmers caring about daylight savings time is farcical, farmers I know use the timekeeping of "crack of dawn" and "sunset".

iirc DST was never about farmers, and always about energy usage (lighting, etc) in the evening Agree I've never met a farmer who cares about DST. Though also, for non-ag farmers, sometimes "crack of dawn" isn't early enough lol. Cow: "Dairy barn has electric lights, why aren't you awake at 4am tending to my needs, Human? Vacation? Lol no, stay here. Every morning. 4am."

DST is not about energy use. If it actually saves energy is debated and depends a lot on the local climate and air conditioning usage etc.

What it is about is moving an extra hour of daylight from say 5:30am-6:30am (when it is only of use to farmers and a few other early risers) to say 7pm-8pm when 95% of the population is still awake.

Re: Never write your own date parsing library

#148

Post by dafelst »

bobsmooth wrote: post #106
quelsolaar wrote: post #100

When ever i see "never implement your own...", i know i want to implement it myself. People say that about hard things, and I only want to do hard things. Nobody wants people who can do easy things, people want people who can do hard things. The only way to learn how to do hard things, is to do hard things, so do the hardest things. So go ahead, write your own date library, your own Unicode font rendering, compiler,…

Solve new hard things instead of solved hard things.

Or you know, just do what you want

Re: Never write your own date parsing library

#149

Post by dracodoc »

quelsolaar wrote: post #100

When ever i see "never implement your own...", i know i want to implement it myself. People say that about hard things, and I only want to do hard things. Nobody wants people who can do easy things, people want people who can do hard things. The only way to learn how to do hard things, is to do hard things, so do the hardest things. So go ahead, write your own date library, your own Unicode font rendering, compiler,…

It's not because it's "hard".

It's all about the nuisance created by human behavior. Calendar, DST, timezone, all the problems you never imagined can happen and can only be met in real life scenarios, and you will meet same problem again, struggle then found out the same problem have been solved long time ago by mature library, and the solution doesn't require any smart or advanced technique, just another corner case.

Re: Never write your own date parsing library

#150

Post by rkagerer »

quelsolaar wrote: post #100

When ever i see "never implement your own...", i know i want to implement it myself. People say that about hard things, and I only want to do hard things. Nobody wants people who can do easy things, people want people who can do hard things. The only way to learn how to do hard things, is to do hard things, so do the hardest things. So go ahead, write your own date library, your own Unicode font rendering, compiler,…

Don't forget to roll your own crypto libraries.
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