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Python developers are embracing type hints

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Re: Python developers are embracing type hints

#321

Post by sota_pop »

the__alchemist wrote: post #319
sota_pop wrote: post #317

Python types - all the onus of static types, with none of the performance! I enjoy packages like pydantic and SOME simple static typing, but if I’m implementing anything truly OOP, I wouldn’t first reach for Python anyway; the language doesn’t even do multiple constructors or public/private props. Edit: as a side note, I was interested to learn that for more verbose type specification, it’s possible to define a type…

There is an important (I would say primary) benefits of types that isn't performance: it's making a program structure [you | your IDE | LLMs] can reason about.

Agreed, it definitely improves my experience when the compiler “knows” the variable types.

Re: Python developers are embracing type hints

#322

Post by coldtea »

sota_pop wrote: post #317

Python types - all the onus of static types, with none of the performance! I enjoy packages like pydantic and SOME simple static typing, but if I’m implementing anything truly OOP, I wouldn’t first reach for Python anyway; the language doesn’t even do multiple constructors or public/private props. Edit: as a side note, I was interested to learn that for more verbose type specification, it’s possible to define a type…

One shouldn't be implementing anything "trully OOP" to begin with...

Re: Python developers are embracing type hints

#323

Post by IshKebab »

1313ed01 wrote: post #193
IshKebab wrote: post #146

Earlier quoted context omitted.

It depends on the project. If you're working always on one project and you have all the time in the world to learn it (or maybe you wrote it), then you can get away with dynamic types. It's still worse but possible. But if you aren't familiar with a project then dynamic typing makes it an order of magnitude harder to navigate and understand. I tried to contribute some features to a couple of big projects - VSCode and…

> In VSCode it was literally right-click->find all references. Flip side of this is that I hate trying to read code written by teams relying heavily on such features, since typically zero time was spent on neatly organizing the code and naming things to make it actually readable (from top to bottom) or grep-able. Things are randomly spread out in tiny files over countless directories and it's a maze you stumble aroun…

That hasn't been my experience at all. I think maybe it feels more like a maze because when you go-to-definition you often don't actually check where you are in the filesystem, so you don't build a mental map of the repo as quickly as you do when you are forced to manually search through all the files. But I wouldn't say that is better.

Kind of like how you don't learn an area when you always use satnav as quickly as you do when you manually navigate with paper maps. But do you want to go back to paper maps? I don't.

Re: Python developers are embracing type hints

#324

Post by coldtea »

Dr_Birdbrain wrote: post #215

I actually don’t like python type hints! At my work we have a jit compiler that requires type hints under some conditions. Aside from that, I avoid them as much as possible. The reason is that they are not really a part of the language, they violate the spirit of the language, and in high-usage parts of code they quickly become a complete mess. For example a common failure mode in my work’s codebase is that some func…

>you better believe that every single admissible type will eventually be fed to this function

That's your problem right there. Why are random callers sending whatever different input types to that function?

That said, there are a few existing ways to define that property as a type, why not a protocol type "Indexable"?

Re: Python developers are embracing type hints

#325

Post by sevensor »

thr0w4w4y1337 wrote: post #231
matusp wrote: post #229

Earlier quoted context omitted.

There is also bunch of prepackaged types, such as collections.abc.Sequence that could be used in this case.

Sequence does not cut it, since the op mentioned int indexed dictionaries. But yeah.

    Sequence[SupportsFloat] | Mapping[int,SupportsFloat]
Whether or not you explicitly write out the type, I find that functions with this sort of signature often end up with code that checks the type of the arguments at runtime anyway. This is expensive and kind of pointless. Beware of bogus polymorphism. You might as well write two functions a lot of the time. In fact, the type system may be gently prodding you to ask yourself just what you think you’re up to here.

Re: Python developers are embracing type hints

#326

Post by coldtea »

Balinares wrote: post #316
zelphirkalt wrote: post #281

Earlier quoted context omitted.

Because the flexibility has been a boon and not a problem. The problem only comes when you try to express everything in the type system, that is third party (the type checkers for it) and added on top.

It's a boon if the goal is to write code then go home. It's a loaded footgun if the goal is to compose a stack and run it in production within SLO. Python type hints manage to largely preserve the flexibility while seriously increasing confidence in the correctness, and lack of crashing corner cases, of each component. There's really no good case against them at this point outside of one-off scripts. (And even there,…

>It's a boon if the goal is to write code then go home. It's a loaded footgun if the goal is to compose a stack and run it in production within SLO.

Never has been an issue in practice...

Re: Python developers are embracing type hints

#327

Post by TZubiri »

bgwalter wrote: post #318
TZubiri wrote: post #287

Earlier quoted context omitted.

So the type is anything that implements the index function ([], or __getitem__), I thnink that's a Sequence, similar to Iterable. >from typing import Sequence >def third(something: Sequence): > return indexable[3] however if all you are doing is just iterate over the thing, what you actually need is an Iterable >from typing import Iterable >def average(something:Iterable): > for thing in something: > ... Statisticall…

That is sort of ironic because the Pythonistas did not leave out any opportunity to criticize Java. Java was developed by world class experts like Gosling and attracted other type experts like Philip Wadler. No world class expert is going to contribute to Python after 2020 anyway, since the slanderous and libelous behavior of the Steering Council and the selective curation of allowed information on PSF infrastructure…

>"Guido: Java is a decent language," 1999

I get the idea that Python and Java went in opposite directions. But I'm not aware of any fight between both languages. I don't think that's a thing either.

Regarding stuff that happens in the 2020. Python was developed in the 90s, python 3 was launched in 2008. Besides some notable PEPs like type hints, WSGI, the rest of development are footnotes. The same goes for most languages (with perhaps the exception of the evergrowing C++), languages make strong bc guarantees and so the bulk of their innovation comes from the early years.

Whatever occurs in the 20th and 30th year of development is unlikely to be revolutionary or very significant. Especially ignoreable is the drama that might emerge in these discussions, slander, libel inter-language criticism?

Just mute that out. I've read some news about some communities like Ruby on Rails or Nix that become overtaken by people and discussions of political nature rather than development, they can just be ignored I think.

Re: Python developers are embracing type hints

#328

Post by [deleted] »

Dr_Birdbrain wrote: post #215

I actually don’t like python type hints! At my work we have a jit compiler that requires type hints under some conditions. Aside from that, I avoid them as much as possible. The reason is that they are not really a part of the language, they violate the spirit of the language, and in high-usage parts of code they quickly become a complete mess. For example a common failure mode in my work’s codebase is that some func…

[deleted]

Re: Python developers are embracing type hints

#329

Post by __MatrixMan__ »

sota_pop wrote: post #317

Python types - all the onus of static types, with none of the performance! I enjoy packages like pydantic and SOME simple static typing, but if I’m implementing anything truly OOP, I wouldn’t first reach for Python anyway; the language doesn’t even do multiple constructors or public/private props. Edit: as a side note, I was interested to learn that for more verbose type specification, it’s possible to define a type…

What does "multiple constructors" buy you that you can't get from multiple static methods that return an object of the enclosing class's type.

Maybe I'm missing out on something cool...

Re: Python developers are embracing type hints

#330

Post by lupusreal »

Types are invaluable in modern code bases because they end up saving a ton of tokens when agentic coding tools are trying to comprehend let alone modify the code. Python isn't intrinsically a great language for LLMs to work with, except in practice it is because they've had a great deal of training data for python. Type hints help a lot with this.
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