But more absurd than creating a global variable if you forget "var/let/const" ? More absurd than "this" being schizophrenic ? More absurd than having no namespace for 20 years ?
That's pushing it.
Of course it does.
$ echo "
> powers_of_x = [lambda x: x^i for i in range(10)]
> [f(2) for f in powers_of_x]
> " > test.py
$ pylint test.py
...
test.py:2:27: W0640: Cell variable i defined in loop (cell-var-from-loop)
...
When concerns are raised about JS, people are quick to answer you are not supposed to use it without modern tooling (Webpack + babel + typescript + eslint + lowdash...), although many devs still do.
Now, I use and teach a lot of JS, and I enjoy many of its modern features. I especially like the object destructuring, it's even better than Python's unpacking.
But objectively, you can get a very decent experience in Python without any kind of tooling. And yet, there is a lot of it if you want to up your game: pylint, black, mypy, jedi, pytest, poetry, etc.
Even if you got the binding right, your powers of 2 would be shot down for being unpythonic anyway due to lambdas being shunned when there are cleaner ways to write things.
powers_of_x makes no sense as a variable name for a list of functions that you have to call in order with the same number to actually get the powers of that number. I get that it’s just a contrived example, but most can be turned into someone more apparent to the reader.
def powers_of_x(x, limit=10):
for i in range(limit):
yield x^i
IMO JS as a language is in a much better place than Python currently. I end up frustrated a fair amount by arcane errors in Python due to less expressive constructs or some wtf issues like unexpected variable scoping within Python modules.
I started to have fun coding in JS the day I accepted it was not Python and that I had to structure and style my code differently.
E.G: in Python you will use iteration a lot. A lot of a lot. But not so many callbacks. The reverse is true in JS.
But even without that, I'm not saying they are comparable. I'm saying the same API will use explicit anonymous callbacks in JS and something else in Python (decorators, subclassing, protocols, generators...). I'm saying that the same API will use __iter__ in Python and something else in JS (type conversion, proxy object, explicit method call...).
E.G, this is a Python pattern you'll find in contextlib or in pytest fixtures:
@somekindofregistration
def foo():
print('code that runs before')
try:
yield
except Stuff:
print('Error handling')
print('code that runs after')
While in JS, you would pass 3 callbacks.
You are misusing the word callback. A callback is a function passed to another thread that will maybe be invoked later as a response (like it calls you back).
Even MDN uses the term callback to describe e.g. the argument to 'map': https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...
In contrast, Lodash goes out of its way not to use the term "callback", presumably to avoid confusion since it's a place where many functions-that-take-a-function-argument do not call the provided function, e.g. https://lodash.com/docs/#curry
>>> (1, 2) == (1, 2)
True
>>> (2, 1) == (1, 2)
False
>>> (1, 2) is (1, 2)
False
>>> isinstance((1, 2), type((1, 2)))
True
I think it's sane.
This. I've made this mistake exactly once in the last 7 years, but that one time almost caused a security issue.