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Pyrefly: A new type checker and IDE experience for Python

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Re: Pyrefly: A new type checker and IDE experience for Python

#51

Earlier quoted context omitted.

This is an open source developer tooling project, not a product which Zuckerberg had anything to do with. What's the point of ignoring it?

Guilt by association is very in vogue these days

These talented engineers could take their skills elsewhere. That's the message.

Re: Pyrefly: A new type checker and IDE experience for Python

#52
post #41

I'm a little worried on behalf of the "Python Language Tooling Team" at Meta, because uv has been so popular, and I wouldn't be surprised if ty wins out in this space. So watch out, or this will become like Atom or Flow, an internal competitor of a technology that is surpassed by the more popular external open source version, leaving the directors/vps muttering to themselves "It's too bad that this team exists at all…

JSX is my favorite thing to come out of Facebook (also the only good thing).

Re: Pyrefly: A new type checker and IDE experience for Python

#53

Why is "written in Rust" a feature to be mentioned? Who cares? So my type checker has memory protection and is compiled. I'm not running my type checker on an embedded system or in a mission critical service. It seems kind of like "written in Erlang". I'd prefer to have non-performance critical code for Python written in Python. That way the broader community can support and extend it.

It makes it easy to find performant and quality software by searching for "[insert tool description] rust", I personally don't mind! Seeing how 95% of the tools I use on the daily are written in Rust, I love finding new ones and am rarely disappointed.

Re: Pyrefly: A new type checker and IDE experience for Python

#54

Why is "written in Rust" a feature to be mentioned? Who cares? So my type checker has memory protection and is compiled. I'm not running my type checker on an embedded system or in a mission critical service. It seems kind of like "written in Erlang". I'd prefer to have non-performance critical code for Python written in Python. That way the broader community can support and extend it.

I feel like 70% of open source projects on GitHub say written in the language that they were written in

Re: Pyrefly: A new type checker and IDE experience for Python

#55
post #30

To repeat an earlier comment of mine from the launch of uv on hn (tl; dr: these new type checkers never support django): The way these type checkers get fast is usually by not supporting the crazy rich reality of realworld python code. The reason we're stuck on mypy at work is because it's the only type checker that has a plugin for Django that properly manages to type check its crazy runtime generated methods. I wis…

1. Maybe it's time to drop the crazy runtime generation and have something statically discoverable, or at least a way to annotate the typing statically. 2. Astral indicated already they plan to just add direct support for Django and other popular languages. 3. As people replied to similar comments on the previous threads (maybe to you?): that's not why ty is fast and why mypy is slow. It's also an easy claim to dispr…

> 1. Maybe it's time to drop the crazy runtime generation and have something statically discoverable, or at least a way to annotate the typing statically.

That, and duck typing, are one of the biggest things that make Python what it is. If I have to drop all that for type checking and rewrite my code, why would I rewrite it in Python?

Re: Pyrefly: A new type checker and IDE experience for Python

#56

Why is "written in Rust" a feature to be mentioned? Who cares? So my type checker has memory protection and is compiled. I'm not running my type checker on an embedded system or in a mission critical service. It seems kind of like "written in Erlang". I'd prefer to have non-performance critical code for Python written in Python. That way the broader community can support and extend it.

Have you used Rust before? As a user, the speed and safety is nice. But as a developer, Rust projects are easier to hack on and contribute to.

That's kind of the whole appeal of Astral. I know Python better than Rust, but it's a lot easier for me to hack on Rust projects. The whole appeal of Astral is that they want to bring Rust-quality tooling to Python.

Re: Pyrefly: A new type checker and IDE experience for Python

#57

Why is "written in Rust" a feature to be mentioned? Who cares? So my type checker has memory protection and is compiled. I'm not running my type checker on an embedded system or in a mission critical service. It seems kind of like "written in Erlang". I'd prefer to have non-performance critical code for Python written in Python. That way the broader community can support and extend it.

I feel like 70% of open source projects on GitHub say written in the language that they were written in

I feel like the likelihood that a project will say what language it is written in is much higher if that language is Rust. I like Rust but I do find this trend a little annoying. (Even though I acknowledge that "written in Rust" probably means the tool is relatively new, not buggy, and easy to use.)

Re: Pyrefly: A new type checker and IDE experience for Python

#59
post #30

Earlier quoted context omitted.

1. Maybe it's time to drop the crazy runtime generation and have something statically discoverable, or at least a way to annotate the typing statically. 2. Astral indicated already they plan to just add direct support for Django and other popular languages. 3. As people replied to similar comments on the previous threads (maybe to you?): that's not why ty is fast and why mypy is slow. It's also an easy claim to dispr…

> 1. Maybe it's time to drop the crazy runtime generation and have something statically discoverable, or at least a way to annotate the typing statically. That, and duck typing, are one of the biggest things that make Python what it is. If I have to drop all that for type checking and rewrite my code, why would I rewrite it in Python?

Having used Python for many years, it’s the least interesting aspect of the language. Almost all such tricks can be done with compile time meta programming, often even without API changes.
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