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Python developers are embracing type hints

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Re: Python developers are embracing type hints

#121

Post by JimDabell »

ninetyninenine wrote: post #112
JimDabell wrote: post #102

Earlier quoted context omitted.

> It can actually roughly reduce dev time by 50% and increase safety by roughly 2x. Type annotations don’t double productivity. What does “increase safety by 2×” even mean? What metric are you tracking there? In my experience, the main non-documentation benefit of type annotations is warning where the code is assuming a value where None might be present. Mixing up any other kind of types is an extremely rare scenario…

>Type annotations don’t double productivity. What does “increase safety by 2×” even mean? What metric are you tracking there? My own anecdotal metric. Isn't that obvious? The initial post was an anecdotal opinion as well. I don't see a problem here. >In my experience, the main non-documentation benefit of type annotations is warning where the code is assuming a value where None might be present. Mixing up any other k…

> My own anecdotal metric. Isn't that obvious? The initial post was an anecdotal opinion as well. I don't see a problem here.

WTF is “an anecdotal metric”‽ That just sounds like an evasive way to say “I want to make up numbers I can’t justify”.

> wtf is direction object? Is it in Cartesian or is it in polar? Is in 2D or 3D?

This seems very domain-specific.

> Most people who complain like you literally have mostly come from a python background where typing isn't used much. Maybe you used types occasionally but not in a big way.

> If you used both untyped languages and typed languages extensively you will know that types are intrinsically better. It's not even a contest. Anyone who still debates this stuff just lacks experience.

I’ve got many years of experience with static typed languages over a 25 year career. Just because somebody disagrees with you, it doesn’t mean they are a clueless junior.

Re: Python developers are embracing type hints

#122

Post by [deleted] »

ninetyninenine wrote: post #112
JimDabell wrote: post #102

Earlier quoted context omitted.

> It can actually roughly reduce dev time by 50% and increase safety by roughly 2x. Type annotations don’t double productivity. What does “increase safety by 2×” even mean? What metric are you tracking there? In my experience, the main non-documentation benefit of type annotations is warning where the code is assuming a value where None might be present. Mixing up any other kind of types is an extremely rare scenario…

>Type annotations don’t double productivity. What does “increase safety by 2×” even mean? What metric are you tracking there? My own anecdotal metric. Isn't that obvious? The initial post was an anecdotal opinion as well. I don't see a problem here. >In my experience, the main non-documentation benefit of type annotations is warning where the code is assuming a value where None might be present. Mixing up any other k…

[deleted]

Re: Python developers are embracing type hints

#123

Post by akdor1154 »

JimDabell wrote: post #102
ninetyninenine wrote: post #84

Earlier 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.

> It can actually roughly reduce dev time by 50% and increase safety by roughly 2x. Type annotations don’t double productivity. What does “increase safety by 2×” even mean? What metric are you tracking there? In my experience, the main non-documentation benefit of type annotations is warning where the code is assuming a value where None might be present. Mixing up any other kind of types is an extremely rare scenario…

> Type annotations don’t double productivity.

Obviously this post is still firmly in made up statistics land, but i agree with OP, in some cases they absolutely do.

New code written by yourself? No, probably not. But refactoring a hairy old enterprise codebase? Absolutely a 2×, 3× multiplier to productivity / time-to-correctness there.

Re: Python developers are embracing type hints

#124

Post by [deleted] »

ninetyninenine wrote: post #82
tecoholic wrote: post #35

I 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…

I learned C++ before learning python as well and python felt like a breath of fresh air. At first I thought it was because of the lack of types. But in actuality the lack of types was a detriment for python. It was an illusion. The reason why python felt so much better was because it had clear error messages and a clear path to find errors and bugs. In C++ memory leaks and seg faults are always hidden from view so EV…

[deleted]

Re: Python developers are embracing type hints

#125

Post by alfons_foobar »

AlienRobot wrote: post #49
tecoholic wrote: post #35

I 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…

Agreed that this "hack" is very ugly!

On the other hand, I tend to take it as a hint that I should look at my module structure, and see if I can avoid the cyclic import (even if before adding type hints there was no error, there still already was a "semantic dependency"...)

Re: Python developers are embracing type hints

#126

Post by Elucalidavah »

seanparsons wrote: post #110

As a static typing advocate I do find it funny how all the popular dynamic languages have slowly become statically typed. After decades of people saying it's not at all necessary and being so critical of statically typed languages. When I was working on a fairly large TypeScript project it became the norm for dependencies to have type definitions in a relatively short space of time.

> how all the popular dynamic languages have slowly become statically typed

Count the amount of `Any` / `unknown` / `cast` / `var::type` in those codebases, and you'll notice that they aren't particularly statically typed.

The types in dynamic languages are useful for checking validity in majority of the cases, but can easily be circumvented when the types become too complicated.

It is somewhat surprising that dynamic languages didn't go the pylint way, i.e. checking the codebase by auto-determined types (determined based on actual usage).

Re: Python developers are embracing type hints

#127

Post by pansa2 »

seanparsons wrote: post #110

As a static typing advocate I do find it funny how all the popular dynamic languages have slowly become statically typed. After decades of people saying it's not at all necessary and being so critical of statically typed languages. When I was working on a fairly large TypeScript project it became the norm for dependencies to have type definitions in a relatively short space of time.

> all the popular dynamic languages have slowly become statically typed

I’ve heard this before, but it’s not really true. Yes, maybe the majority of JavaScript code is now statically-typed, via Typescript. Some percentage of Python code is (I don’t know the numbers). But that’s about it.

Very few people are using static typing in Ruby, Lua, Clojure, Julia, etc.

Re: Python developers are embracing type hints

#128

Post by vladms »

seanparsons wrote: post #110

As a static typing advocate I do find it funny how all the popular dynamic languages have slowly become statically typed. After decades of people saying it's not at all necessary and being so critical of statically typed languages. When I was working on a fairly large TypeScript project it became the norm for dependencies to have type definitions in a relatively short space of time.

I like static types but advocating for enforcing them in any situation is different. Adding them when you need (Python currently) seems a better strategy than forcing you to set them always (Typescript is in between as many times it can determine them).

Many years ago I felt Java typing could be overkill (some types could have been deduced from context and they were too long to write) so probably more an issue about the maturity of the tooling than anything else.

Re: Python developers are embracing type hints

#129

Post by yurishimo »

adalacelove wrote: post #118
seanparsons wrote: post #110

As a static typing advocate I do find it funny how all the popular dynamic languages have slowly become statically typed. After decades of people saying it's not at all necessary and being so critical of statically typed languages. When I was working on a fairly large TypeScript project it became the norm for dependencies to have type definitions in a relatively short space of time.

People adapt to the circumstances. A lot of Python uses are no longer about fast iteration on the REPL. Instead of that we are shipping Python to execute in clusters on very long running jobs or inside servers. It's not only about having to start all over after hours, it's simply that concurrent and distributed execution environments are hostile to interactive programming. Now you can't afford to wait for an exceptio…

PHP is a great example of the convergence of interfaces. Now they have different “PSR” standards for all sorts of things. There is one for HTTP clients, formatting, cache interfaces, etc. As long as your library implements the spec, it will work with everything else and then library authors are free to experiment on the implementation and contribute huge changes to the entire ecosystem when they find a performance breakthrough.

Types seem like a “feature” of mature software. You don’t need to use them all the time, but for the people stuck on legacy systems, having the type system as a tool in their belt can help to reduce business complexity and risk as the platform continues to age because tooling can be built to assert and test code with fewer external dependencies.

Re: Python developers are embracing type hints

#130

Post by flohofwoe »

seanparsons wrote: post #110

As a static typing advocate I do find it funny how all the popular dynamic languages have slowly become statically typed. After decades of people saying it's not at all necessary and being so critical of statically typed languages. When I was working on a fairly large TypeScript project it became the norm for dependencies to have type definitions in a relatively short space of time.

OTH I only came to realize that I actually like duck typing in some situations when I tried to add type hints to one of my Python projects (and then removed them again because the actually important types consisted almost entirely of sum types, and what's the point of static typing if anything is a variant anyway).

E.g. when Python is used as a 'scripting language' instead of a 'programming language' (like for writing small command line tools that mainly process text), static typing often just gets in the way. For bigger projects where static typing makes sense I would pick a different language. Because tbh, even with type hints Python is a lousy programming language (but a fine scripting language).

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