This is clever and worth reading, and I didn't know about some of the 3.12 changes. Overall though I think the author has some pain in store. Using functions like map in Python result in Python iterators which are mutable objects (they consume and throw away an element of the sequence on each iteration) and this often causes hassles unless you convert them to lists (which burns memory and maybe does unnecessary computation). Also, Python's type checking stuff (at least Mypy) are mostly a bug catching feature. They aren't like a real type system though: mistyped programs can still get through, and properly typed ones can get flagged. It's better than nothing and I use it, but it's nowhere near e.g. Haskell.
this post was submitted on 24 May 2024
43 points (97.8% liked)
Python
6331 readers
305 users here now
Welcome to the Python community on the programming.dev Lemmy instance!
π Events
Past
November 2023
- PyCon Ireland 2023, 11-12th
- PyData Tel Aviv 2023 14th
October 2023
- PyConES Canarias 2023, 6-8th
- DjangoCon US 2023, 16-20th (!django π¬)
July 2023
- PyDelhi Meetup, 2nd
- PyCon Israel, 4-5th
- DFW Pythoneers, 6th
- Django Girls Abraka, 6-7th
- SciPy 2023 10-16th, Austin
- IndyPy, 11th
- Leipzig Python User Group, 11th
- Austin Python, 12th
- EuroPython 2023, 17-23rd
- Austin Python: Evening of Coding, 18th
- PyHEP.dev 2023 - "Python in HEP" Developer's Workshop, 25th
August 2023
- PyLadies Dublin, 15th
- EuroSciPy 2023, 14-18th
September 2023
- PyData Amsterdam, 14-16th
- PyCon UK, 22nd - 25th
π Python project:
- Python
- Documentation
- News & Blog
- Python Planet blog aggregator
π Python Community:
- #python IRC for general questions
- #python-dev IRC for CPython developers
- PySlackers Slack channel
- Python Discord server
- Python Weekly newsletters
- Mailing lists
- Forum
β¨ Python Ecosystem:
π Fediverse
Communities
- #python on Mastodon
- c/django on programming.dev
- c/pythorhead on lemmy.dbzer0.com
Projects
- PythΓΆrhead: a Python library for interacting with Lemmy
- Plemmy: a Python package for accessing the Lemmy API
- pylemmy pylemmy enables simple access to Lemmy's API with Python
- mastodon.py, a Python wrapper for the Mastodon API
Feeds
founded 1 year ago
MODERATORS
I don't think I would call this functional. Python is decidedly not at all functional - there's no way to declare arbitrary functions inline, no chaining of map/filter etc.
But the static types are definitely welcome. I didn't know about the type keyword. Apparently it makes it support forward references.
like everything in python, to achieve functional you must first import functional
You're still limited by lambda expressions though. And in general the language is still statement based, not expression based. You can't do a = if foo then x else y type things (except for the one-off and backwards x if foo else y; they were so close!).
"a = x if foo else y" is a perfectly cromulent statement!
It's not. In functional languages there's no special case like this. All if-elses are expressions. It's far superior. For example how do you do this with Python's if-else expression?
let x = if foo {
let y = bar();
baz();
y
} else {
z
}
x = foo(y:=bar(), baz(), y) or z should work assuming foo bar and baz are functions being called?
if this is setting y to the effect of bar() + running baz after, then:
x = [bar(), baz()][0] or z
might work
and if you need y to be defined for later use:
x = [(y:=bar()), baz()][0] or z
but thats from memory, not sure if that will even run as written.
if I get to a real computer I'll try that with an actual if statement instead of a bastardized ternary.foo isn't a function, it's a bool. But in any case, as you can see the answer is "with terrible hacks". Python is not a functional language. It is imperative.
Yeah, never said it was, just that if you really want to emulate that style you mostly can.
Does it have higher-order functions? Yes, therefore you can use it to do functional programming.
Everything else is syntactic sugar.
Functional programming doesn't just mean higher order functions. There's a range of other features that it implies.
This is quite cool and a very interesting read. I'm not sure if it's something I would want to use in a real project, because it looks like you're basically inventing a new language within Python's type system itself, which is a little weird. That said, I feel like I learned a lot from reading this, and it was a very interesting demonstration of what you can do with Python's type-checking system.