pyre-check VS pyright

Facebook/Instagram uses Pyre which is a typechecker for Python.

I'd be curious if the pyre-check compilation is any faster for you either by removing the inlining optimization flag (the `-Oclassic` here https://github.com/facebook/pyre-check/blame/36243764ab81a82...) or whether there's a way to compile pyre-check to bytecode instead of the native compilation step (which unfortunately it looks like there's no easy way to modify pyre-check's build config to do so).

I must be doing something wrong.

[1] https://github.com/facebook/pyre-check

Some other good alternatives for type checking are Pyright (which is seen in VSCode via Microsofts PyLance plugin) and Pyre.

Sorry if this is something that you’re already aware of but there already exists a Python-related project with the same name which may lead to confusion. https://pyre-check.org

I'm using VSCodium (VSCode without Microsoft's telemetry) which doesn't work with pylance, Microsoft's Python language server. It seems like the two main alternative contenders are pyright and pylsp. I've been trying pyright, which has an extension, but it doesn't seem to support docstrings on all packages. I couldn't find any configuration options for setting an alternative language server in VSCode. Anyone have some tips on how to set up pylsp?

While mypy is the (and also my) go-to solution, I recently found pyright but haven't used it yet.

Every point in this blog post strikes me as either (1) unaware of the tooling around python typing other than mypy, or (2) a criticism of static-typing-bolted-on-to-a-dynamically-typed-language, rather than Python's hints. Regarding (1), my advise to OP is to try out Pyright, Pydantic, and Typeguard. Pyright, especailly, is amazing and makes the process of working with type hints 2 or 3 times smoother IMO. And, I don't think points that fall under (2) are fair criticisms of type *hints*. They are called hints for a reason.

Otherwise, here's a point-by-point response, either recommending OP checks out tooling, or showing that the point being made is not specific to Python.

> type hints are not binding.

There are projects [0][1] that allow you to enforce type hints at runtime if you so choose.

It's worth mentioning that this is very analogous to how Typescript does it, in that type info is erased completely at runtime.

> Type checking is your job after all, ...[and that] requires maintenance.

There are LSPs like Pyright[2] (pyright specifically is the absolute best, IMO) that report type errors as you code. Again, this is very very similar to typescript.

> There is an Any type and it renders everything useless

I have never seen a static-typing tool that was bolted on to a dynamically typed language, without an `Any` type, including typescript.

> Duck type compatibility of int and float

The author admits that they cannot state why this behavior is problematic, except for saying that it's "ambiguous".

> Most projects need third-party type hints

Again, this is a criticism of all cases where static types are bolted on dynamically typed languages, not Python's implementation specifically.

> Sadly, dataclasses ignore type hints as well

Pydantic[3] is an amazing data parsing library that takes advantage of type hints, and it's interface is a superset of that of dataclasses. What's more, it underpins FastAPI[4], an amazing API-backend framework (with 44K Github stars).

> Type inference and lazy programmers

The argument of this section boils down to using `Any` as a generic argument not being an error by default. This is configurable to be an error both in Pyright[5], and mypy[6].

> Exceptions are not covered [like Java]

I can't find the interview/presentation, but Guido Van Rossum specifically calls out Java's implementation of "exception annotations" as a demonstration of why that is a bad idea, and that it would never happen in Python. I'm not saying Guido's opinion is the absolute truth, but just letting you know that this is an explicit decision, not an unwanted shortcoming.

[0] https://github.com/RussBaz/enforce

[1] https://github.com/agronholm/typeguard

[2] https://github.com/microsoft/pyright

[3] https://pydantic-docs.helpmanual.io

[4] https://github.com/tiangolo/fastapi

[5] https://github.com/microsoft/pyright/blob/main/docs/configur...

[6] https://mypy.readthedocs.io/en/stable/config_file.html#confv...

MyPy isn’t the only checker of course, there’s also Microsoft’s Pyright, among others. Pyright is fast and natively integrated in Microsoft’s Pylance VSCode extension, so these days I use Pyright’s type checking in real time even when I can’t be bothered to set up MyPy (no difficult, just not important for, say, <1000 line scripts).

https://github.com/microsoft/pyright

https://marketplace.visualstudio.com/items?itemName=ms-pytho...

pyright is a command line program https://github.com/microsoft/pyright

in my experience it's a far better type checker than mypy, which tends to silently not check things without you ever realising

There's nothing to trust, pyright is entirely open source and you can check it yourself: https://github.com/Microsoft/pyright

Turns out it was a bug in pyright - the first example never type checked with mypy. :/

From: https://github.com/microsoft/pyright/blob/main/docs/configuration.md

This discussion probably gives more context than I ever could: https://github.com/microsoft/pyright/issues/1118