Hacker News Reader

Comment by redsymbol | Hacker News Reader

Important to realize glyph's twitter followers are not representative of all Python users.

In general, people who follow him are going to be more "into" Python than someone who just uses it to get their job done, and thus more likely to use optional tooling with a large overhead like mypy.

That will skew the results in favor of mypy in this poll. Though the poll getting on the HN front page will balance that somewhat.

View on HN

I'm just using it to get my job done, and really couldn't imagine working with Python without it.

I'd consider static type checker as optional if you are playing around with small or throwaway scripts, but for any half serious project, it should be a requirement.

IME I don't consider it slow, and it's definitely not visibly slower than pylint, flake8, or similar tools for other languages.

Dropbox, which has one of the biggest Python codebases, uses it, and most mypy maintainers including Guido work there.

The biggest problem with mypy is that it's written in python. It's slow. It needs to be rewritten in rust or go to make it faster like how js ecosystem is moving in that direction. All the tooling is moved to faster compiled languages.

mypy has implementations in other languages – PyCharm's is in Java, Facebook's Pyre's is in OCaML https://github.com/facebook/pyre-check

Those tools are not re-implementations of mypy, but their own type checkers. Pyre doesn't necessarily have all the features of mypy and vice versa.

mypy is actually compiled via mypyc, which should be a few times faster than interpreted Python https://github.com/python/mypy/tree/master/mypyc

Initial type checking with mypy is slow, but if you use mypy-daemon each check after that becomes pretty much instantaneous, even on 10M+ line code bases.

> Dropbox, which has one of the biggest Python codebases, uses it, and most mypy maintainers including Guido work there.

Guido hasn't worked at Dropbox since 2019. He retired for a bit, but is now in the Developer Division at Microsoft.

My bad, I just checked http://mypy-lang.org/about.html, which appears to be outdated.

Yea, it may slightly slow down the initial draft due to needing to type a little bit more, but it helps speed up maintainability and readability a ton and it helps eliminate a bunch of bugs so I think it has definitely increased productivity in my experience.

Arguably that applies to all social media ;)

I see a lot of sort of 'programming culture' for given languages, practices, even discussion of working conditions and etc that on social media are taken as standard operating procedure. Highly active and even highly knowledgeable folks seem to portray various practices and etc are a given ... that I suspect are actually outliers.

I agree listen to the heavy weights on these sorts of things. But a poll open to everyone is pretty useless.

One of the first things you learn in theoretical sampling classes is that polls where people self select to participate (like twitter polls) are garbage

The results are good, they are just, "of the population that uses twitter" ...

What I would really be interested in, is do library developers use or intend to use mypy? Because if your libs are typed checked and your APIs are well constructed, a lot of that safety will flow to the clients.

Maybe those 40% would love to use it if something was changed or fixed. I think these numbers are frankly amazing, a year from now we reach an inflection point where mypy is used by the majority of some segment of the Python developer ecosystem.

Yup agree. People who follow him are more "into" python async stuff.

Reply on news.ycombinator.com