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Python type hints may not be not for me in practice

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Re: Python type hints may not be not for me in practice

#71

Post by IshKebab »

hbrn wrote: post #67
belorn wrote: post #37

Earlier quoted context omitted.

Looking at that blog post, I find it illustrative in how people who like strong types and people who dislike strong types are addressing different form of bugs. If the main types of issues comes from bugs like 1 + "2" == 12" , then strong types is a big help. It also enables many developers who spend the majority of time in a programming editor to quickly get automatic help with such bugs. The other side is those peo…

What's even worse, when typing is treated as an indisputable virtue (and not a tradeoff), pretty much every team starts sacrificing readability for the sake of typing. And lo and behold, they end up with _more_ design bugs. And the sad part is that they will never even recognize that too much typing is to blame.

Nonsense. You might consider it a tradeoff, but it's a very heavily skewed one. Minor downsides on one side, huge upsides on the other.

Also I would say type hints sacrifice aesthetics, not readability. Most code with type hints is easier to read, in the same way that graphs with labelled axes and units are easier to read. They might have more "stuff" there which people might think is ugly, but they convey critical information which allows you to understand the code.

Re: Python type hints may not be not for me in practice

#72

Post by IshKebab »

hbrn wrote: post #63
tasn wrote: post #21

The Python type system is pretty bad, but it's still 100x better than not using types. We are heavy users of the (Rust) type system at Svix, and it's been a godsend. I wrote about it here https://www.svix.com/blog/strong-typing-hill-to-die-on/ We also use Python in some places, including the shitty Python type-system (and some cool hackery to make SQLAlchemy feel very typed and work nicely with Pydantic).

> Writing software without types lets you go at full speed. Full speed towards the cliff. Isn't it strange that back when Python (or Ruby) didn't even have type hints (not type checkers, type hints!), it would easily outperform pretty much every heavily typed language? Somehow when types weren't an option we weren't going towards the cliff, but now that they are, not using them means jumping off a cliff? Something do…

> when types weren't an option we weren't going towards the cliff

Erm yes we were. Untyped Python wasn't magically tolerable just because type hints hadn't been implemented yet.

Re: Python type hints may not be not for me in practice

#73

Post by IshKebab »

ansgri wrote: post #41
terminalbraid wrote: post #25

Sometimes I feel like we need an analog to javascript/typescript. Ptypethon if you will.

Absolutely. The main problem with python typing is that checking types is optional. A dialect with mandatory types (with inference) and runtime/load-time checking would be great.

Checking types is optional with Typescript too. We don't need another type annotation syntax for Python. The existing one is fine.

Re: Python type hints may not be not for me in practice

#74

Post by Neywiny »

The note about creating your own data types is interesting. I used to be heavily dependent on tuples. Admittedly dicts would've saved me here but I liked the efficiency of numeric indexing. Anyway, any time I changed ordering or anything I'd have countless headaches. I started using dataclasses and never looked back. I love turning the type checker on in vscode and seeing it correctly catch future issues. Only problem is when libraries are indirectly hinted, as others have pointed out

Re: Python type hints may not be not for me in practice

#75

Post by otherme123 »

rty32 wrote: post #62
belorn wrote: post #37

Earlier quoted context omitted.

Looking at that blog post, I find it illustrative in how people who like strong types and people who dislike strong types are addressing different form of bugs. If the main types of issues comes from bugs like 1 + "2" == 12" , then strong types is a big help. It also enables many developers who spend the majority of time in a programming editor to quickly get automatic help with such bugs. The other side is those peo…

> The other side is those people who do not find those kind of bugs annoying Anecdotally, I find these are the same people who work less effectively and efficiently. At my company, I know people who mainly use Notepad++ for editing code when VSCode (or another IDE) is readily available, who use print over debuggers, who don't get frustrated by runtime errors that could be caught in IDEs, and who opt out of using codi…

>these people don't push code out as fast they could.

Well, one of my coworkers pushes code quite fast, and also he is the one who get rejected more often because he keep adding .tmp, .pyc and even .env files to his commits. I guess "git add asterisk" is faster, and thus more efficient, than adding files slowly or taking time to edit gitignore.

Not so long ago I read a history here in HN about a guy that first coded in his head, then wrote everything in paper, and finally coded in a computer. It compiled without errors. Slow pusher? Inefficient?

Re: Python type hints may not be not for me in practice

#76

Post by hbrn »

IshKebab wrote: post #71
hbrn wrote: post #67

Earlier quoted context omitted.

What's even worse, when typing is treated as an indisputable virtue (and not a tradeoff), pretty much every team starts sacrificing readability for the sake of typing. And lo and behold, they end up with _more_ design bugs. And the sad part is that they will never even recognize that too much typing is to blame.

Nonsense. You might consider it a tradeoff, but it's a very heavily skewed one. Minor downsides on one side, huge upsides on the other. Also I would say type hints sacrifice aesthetics, not readability. Most code with type hints is easier to read, in the same way that graphs with labelled axes and units are easier to read. They might have more "stuff" there which people might think is ugly, but they convey critical i…

> Most code with type hints is easier to read

That has not been my experience in the past few years.

I've always been a fan of type hints in Python: intention behind them was to contribute to readability and when developer had that intention in mind, they worked really well.

However, with the release of mypy and Typescript, engineering culture largely shifted towards "typing is a virtue" mindset. Type hints are no longer a documentation tool, they are a constraint enforcing tool. And that tool is often at odds with readability.

Readability is subjective and ephemeral, type constraints (and intellisense) are very tangible. Naturally, developers are failing to find balance between the two.

Re: Python type hints may not be not for me in practice

#77

Post by joeyagreco »

> After the code has stabilized I can probably go back to write type hints [...] but I'm not sure that this would provide very much value.

I think most developers who revisit their projects 6+ months later would disagree with the second part of this statement.

My typical flow for "quick scripts" is:

on first pass I'll add basic type hints (typing ":str" after a func param takes .2 seconds)

for more complex data structures (think a json response from an api), dict (or typing.Dict) work fine

if you want a Python project to be maintainable, type hints are a requirement imho.

Re: Python type hints may not be not for me in practice

#79

Post by hbrn »

IshKebab wrote: post #72
hbrn wrote: post #63

Earlier quoted context omitted.

> Writing software without types lets you go at full speed. Full speed towards the cliff. Isn't it strange that back when Python (or Ruby) didn't even have type hints (not type checkers, type hints!), it would easily outperform pretty much every heavily typed language? Somehow when types weren't an option we weren't going towards the cliff, but now that they are, not using them means jumping off a cliff? Something do…

> when types weren't an option we weren't going towards the cliff Erm yes we were. Untyped Python wasn't magically tolerable just because type hints hadn't been implemented yet.

How come all those unicorns were built with intolerable Python/Ruby, not Java/C#/Go?

https://charliereese.ca/y-combinator-top-50-software-startup...

Re: Python type hints may not be not for me in practice

#80

Post by zo1 »

CJefferson wrote: post #54
Myrmornis wrote: post #29

Earlier quoted context omitted.

Can you give some examples of how the Python type system is disappointing you?

Mainly, the seems to be no way, in a dynamic language, to dynamically check if functions get the right types. To me, this means I don't really understand the python type hinting at all, as adding hints to just one or two functions provides no value to me at all. I assume I must be not using them usefully, as I've tried adding type hints to some projects and they just seemed to do nothing useful.

How to tell me you use VScode without telling me you use VScode.
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