With duck typing, you don’t need type hints. You’re just supposed to use the variable however you “feel” it should be used when you’re using it, and it automagically just works!!! Try it! /s
Python developers are embracing type hints
91–100 of 581 posts
Re: Python developers are embracing type hints
#92It’s ok. The mild ground of typing feels pretty clunky to me though
Definitely not a best of both world type outcome
Re: Python developers are embracing type hints
#93Earlier quoted context omitted.
With the newest Python versions, most of the time I don't need typing imports!
Yeah post 3.10 you don't need Union, Optional, List, Duct, Tuple. Any still necessary when you want to be permissive, and I'm still hoping for an Unknown someday...
I am glad they improved this but I still like Optional[], and to a lesser extent, Union[]. It's much more readable to have Optional[str] compared to str | None.
Re: Python developers are embracing type hints
#94The thing that finally got me on board with optional type hints in Python was realizing that they're mainly valuable as documentation. But it's really valuable documentation! Knowing what types are expected and returned just by looking at a function signature is super useful.
This is a naive realization. When type checking is used to the maximum extent they become as just as important as unit testing. It is an actual safety contribution to the code. Many old school python developers don't realize how important typing actually is. It's not just documentation. It can actually roughly reduce dev time by 50% and increase safety by roughly 2x.
Static type checking (which is what I assume you mean by "typing") can also be a massive pain in the ass that stands in the way of incremental development, even if the end-goal is to ship an api with clear type signatures.
There are developers who design apis by trying to figure out readable invocations. These developers discover, rather than design, type hierarchies and library interfaces.
> Many old school python developers don't realize how important typing actually is.
I don't think this is true. There's simply a communication breakdown where type-first developers don't see the benefits of disabling static checking to design interfaces, and interface-first developers don't see why they should put static checking ahead of interface iteration speed.
Re: Python developers are embracing type hints
#95I was extremely skeptical when typing was introduced. What's the point if runtime ignores them. I forced myself to use them as documentation and now I'm on the other side of the spectrum, all code should have them. It already helped me a lot during refactors and I always wished more code had types. I think the same is true for AIs, they will benefit from having the types explicitly said. It's a shame they currently default to untyped Python.
Re: Python developers are embracing type hints
#96The thing that finally got me on board with optional type hints in Python was realizing that they're mainly valuable as documentation. But it's really valuable documentation! Knowing what types are expected and returned just by looking at a function signature is super useful.
Decent argument in principle. It still sucks for non-obvious types though: https://old.reddit.com/r/Python/comments/10zdidm/why_type_hi... Edit: Yes, one can sometimes go with Any, depending on the linter setup, but that's missing the point, isn't it?
The correct response to this is to figure what is the use case for your function: IE: add two numbers. Set the input and output as decimal and call it a day
Re: Python developers are embracing type hints
#97I started using Python at work with type hints. I am very satisfied.
Re: Python developers are embracing type hints
#98The thing that finally got me on board with optional type hints in Python was realizing that they're mainly valuable as documentation. But it's really valuable documentation! Knowing what types are expected and returned just by looking at a function signature is super useful.
This is a naive realization. When type checking is used to the maximum extent they become as just as important as unit testing. It is an actual safety contribution to the code. Many old school python developers don't realize how important typing actually is. It's not just documentation. It can actually roughly reduce dev time by 50% and increase safety by roughly 2x.
It's claims like that which used to put me off embracing type hints!
I'd been programming for 20+ years and I genuinely couldn't think of any situations where I'd had a non-trivial bug that I could have avoided if I'd had a type checker - claims like "reduce dev time by 50%" didn't feel credible to me, so I stuck with my previous development habits.
Those habits involved a lot of work performed interactively first - using the Python terminal, Jupyter notebooks, the Firefox/Chrome developer tools console. Maybe that's why I never felt like types were saving me any time (and in fact were slowing me down).
Then I had my "they're just interactive documentation" realization and finally they started to click for me.
Re: Python developers are embracing type hints
#99I love typing in Python. I learnt programming with C++ and OOPs. It was freeing when I took up Python to note care about types, but I have come to enjoy types as I got older. But, boy have we gone overboard with this now? The modern libraries seem to be creating types for the sake of them. I am drowning in nested types that seem to never reach native types. The pain is code examples of the libraries don’t even show t…
My love for python was critically hurt when I learned about typing.TYPE_CHECKING. For those unaware, due to the dynamic nature of Python, you declare a variable type like this foo: Type This might look like Typescript, but it isn't because "Type" is actually an object. In python classes and functions are first-class objects that you can pass around and assign to variables. The obvious problem of this is that you can…
There's actually another issue with ForwardRefs. They don't work in the REPL. So this will work when run as a module:
def foo() -> "Bar":
return Bar()
However, all of these issues should be fixed in 3.14 with PEP649 and PEP749:
> At compile time, if the definition of an object includes annotations, the Python compiler will write the expressions computing the annotations into its own function. When run, the function will return the annotations dict. The Python compiler then stores a reference to this function in __annotate__ on the object.
> This mechanism delays the evaluation of annotations expressions until the annotations are examined, which solves many circular reference problems.
Re: Python developers are embracing type hints
#100Earlier quoted context omitted.
This is a naive realization. When type checking is used to the maximum extent they become as just as important as unit testing. It is an actual safety contribution to the code. Many old school python developers don't realize how important typing actually is. It's not just documentation. It can actually roughly reduce dev time by 50% and increase safety by roughly 2x.
Static type checking (which is what I assume you mean by "typing") can also be a massive pain in the ass that stands in the way of incremental development, even if the end-goal is to ship an api with clear type signatures. There are developers who design apis by trying to figure out readable invocations. These developers discover, rather than design, type hierarchies and library interfaces. > Many old school python d…
>There are developers who design apis by trying to figure out readable invocations. These developers discover, rather than design, type hierarchies and library interfaces.
No, you're one of the old school python developers. Types don't hinder creativity, they augment it. The downside is the slight annoyance of updating a type definition and the run time definition vs. just updating the runtime definition.
Let me give you an example of how it hinders creativity.
Let's say you have a interface that is immensely complex. Many nested structures thousands of keys, and let's say you want to change the design by shifting 3 or 4 things around. Let's also say this interface is utilized by hundreds of other methods and functions.
When you move 3 or 4 things around in a complex interface you're going to break a subset of those hundreds of other methods or functions. You're not going to know where they break if you don't have type checking enabled. You're only going to know if you tediously check every single method/function OR if it crashes during runtime.
With a statically typed definition you can do that change and the type checker will identify EVERY single place where an additional change to the methods that use that type needs to be changed as well. This allows you to be creative and make any willy nilly changes you want because you are confident that ANY change will be caught by the type checker. This Speeds up creativity, while without it, you will be slowed down, and even afraid to make the breaking change.
You are basically the stereotype I described. An old school python developer. Likely one who got used to programming without types and now hasn't utilized types extensively enough to see the benefit.
>I don't think this is true. There's simply a communication breakdown where type-first developers don't see the benefits of disabling static checking to design interfaces, and interface-first developers don't see why they should put static checking ahead of interface iteration speed.
This is true. You're it. You just don't know it. When I say these developers don't know I'm literally saying they think like you and believe the same things you believe BECAUSE they lack knowledge and have bad habits.
The habit thing is what causes the warped knowledge. You're actually slowed down by types because you're not used to it as you spent years coding in python without types so it's ingrained for you to test and think without types. Adding additional types becomes a bit of a initial overhead for these types of people because their programming style is so entrenched.
Once you get used to it and once you see that it's really just a slight additional effort, than you will get it. But it takes a bit of discipline and practice to get there.