[MrJohz]

The Date example is possibly an even better example of why dependencies that get hard problems right are so important. If Python's datetime library is bad, Date is truly terrible. Every time I have used it I have regretted it long term (including when using it in combination with date-fns in the hope that that makes it usable). And in the end, trying to keep things simple with Date has caused more technical debt than using a sensible dependency.

Some problems simply require using the right tools. They aren't necessarily hard, but they will be if you try to hammer a nail in with a screwdriver. The Date API, and to a certain extent Python's datetime module, are screwdrivers for a nail-shaped problem.

The rest of your example seem to have more to do with bad dependency practices than using dependencies in the first place. If you are going to include a dependency, think about it, consider whether it's worth it, document that decision, and then consistently use that dependency. Just because you've seen projects use dependencies poorly doesn't mean dependents are bad by themselves.

[Gare]

Fortunately, JS is getting Temporal, which will be great. No such thing on the horizon for Python yet.

[MrJohz]

Well, there's libraries like this one, which is the point here.

And even in JS, Temporal won't be available broadly for a good while yet (it will probably be rolling out in Firefox in a couple of months' time, but in Safari it's still behind a feature flag, and I don't think there's even a feature-flagged implementation for Chrome yet). In the meantime, it makes sense to use a polyfill — again a library.

By all means choose your dependencies wisely, but the point I'm trying to make is that very often a sensible use of dependencies will reduce your technical debt, and attempting to use bad approaches to complex topics just because they're built into the standard library will cause so many problems down the line.

[Gare]

I fully agree with that. Just a bit disappointed that Python is not even considering to fix/replace it's problematic datetime library (as far as I know). Excellent third-party library is good, but an excellent standard library is even better!

[burntsushi]

Maybe this is the first step toward that future.

In Temporal's case, it takes significant inspiration from several existing datetime libraries in Javascript. Those were all stepping stones (among others) that led to Temporal.

[ljm]

I used a bad example with the Date API, except that, say, using moment or date-fns and sticking to it would be better than jumbling them up. If you’re going to do a migration from one to the other then it has to be committed to.

Dependencies themselves can’t be good or bad. They only acquire that property in the context of the dependent codebase. And a codebase that you can’t spin up from scratch or easily grok because of its approach (or lack thereof) to dependencies is almost certainly on the bad end of the spectrum.

I’ve seen this destroy some python codebases internally. In fact, my choice of a JS example was unfair because it becomes an absolute shitshow in python once you have dependencies and transitive dependencies with very tight version constraints.