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> high-brow discussion of US politics

lol, implying you'll find that on HN


I write a decent amount of Python, but find the walrus operator unintuitive. It's a little funky that API_KEY is available outside of the `if`, perhaps because I had first seen the walrus operator in golang, which restricts the scope to the block.


This isn't really unique to the walrus operator, it's just a general python quirk (albeit one I find incredibly annoying). `for i in range(5): ...` will leave `i` bound to 4 after the loop.


Oddly enough, "except" variables don't remain bound!

    try:
        x = int('cat')
    except Exception as e:
        pass
    print(e)  # <- NameError: name 'e' is not defined
So, it appears Python actually has three variable scopes (global, local, exception block)?


Nope, it's more complicated than that:

    e = 'before'
    try:
        x = int('cat')
    except Exception as e:
        e2 = e
        print(e)
    print(e2) # <- This works!
    print(e)  # <- NameError: name 'e' is not defined
It's not a scoping thing, the bound exception variable is actually deleted after the exception block, even if it was already bound before!


lol - raku maybe weird, but at least it has sane variable scoping


Also true of JavaScript pre-ES5, another language that on first glance seems to only have function scope: it actually does have block scope, but only for variables introduced in `catch` blocks. AFAIU that was the standard way for a dumb transpiler to emulate `let`.


I wonder if that was ever popular, considering the deoptimization effects of try/catch, and given that block scope can also be managed by renaming variables.


exceptions being the exception is funny somehow


very recursive


you can say that again.


Exception blocks don't create a different scope. Instead, the name is explicitly (well, implicitly but deliberately) deleted from the scope after the try/except block runs. This happens because it would otherwise produce a reference cycle and delay garbage collection.

https://stackoverflow.com/questions/24271752

https://docs.python.org/3/reference/compound_stmts.html#exce...


This is the type of things that make me roll my eyes at all the wtf JavaScript posts[0], yes there are a lot of random things that happen with type conversions and quite a few idiosyncrasies (my favourite is that document.all is a non empty collection that is != from false but convert to false in an if)

But the language makes sense at a lower level, scopes, values, bindings have their mostly reasonable rules that are not hard to follow.

In comparison python seems like an infinite tower of ad-hoc exceptions over ad-hoc rules, sure it looks simpler but anywhere you look you discover an infinite depth of complexity [1]

[0] and how half of the complaints are a conjugation of "I don't like that NaNs exist

[1] my favourite example is how dunder methods are a "synchronized view" of the actual object behaviour, that is in a + b a.__add__ is never inspected, instead at creation time a's add behaviour is defined as its __add__ method but the association is purely a convention, eg any c extension type need to reimplement all these syncs to expose the correct behaviour and could for funzies decide that a type will use __add__ for repr and __repr__ for add


> yes there are a lot of random things that happen with type conversions and quite a few idiosyncrasies... the language makes sense at a lower level, scopes, values, bindings have their mostly reasonable rules

The "random things" make it practically impossible to figure out what will happen without learning a whole bunch of seemingly arbitrary, corner-case-specific rules (consider the jsdate.wtf test currently making the rounds). And no, nobody is IMX actually simply complaining about NaNs existing (although the lack of a separate integer type does complicate things).

Notice that tests showcasing JavaScript WTFery can work just by passing user data to a builtin type constructor. Tests of Python WTFery generally rely on much more advanced functionality (see e.g. https://discuss.python.org/t/quiz-how-well-do-you-know-pytho...). The only builtin type constructor in Python that I'd consider even slightly surprising is the one for `bytes`/`bytearray`.

Python's scoping is simple and makes perfect sense, it just isn't what you're used to. (It also, unlike JavaScript, limits scope by default, so your code isn't littered with `var` for hygiene.) Variables are names for objects with reference semantics, which are passed by value - exactly like `class` types in C# (except you don't have to worry about `ref`/`in`/`out` keywords) or non-primitives in Java (notwithstanding the weird hybrid behaviour of arrays). Bindings are late in most places, except notably default arguments to functions.

I have no idea what point you're trying to make about __add__; in particular I can't guess what you think it should mean to "inspect" the method. Of course things work differently when you use the C API than when you actually write Python code; you're interacting with C data structures that aren't directly visible from Python.

When you work at the Python level, __add__/__iadd__/__radd__ implement addition, following a well-defined protocol. Nothing happens "at creation time"; methods are just attributes that are looked up at runtime. It is true that the implementation of addition will overlook any `__add__` attribute attached directly to the object, and directly check the class (unlike code that explicitly looks for an attribute). But there's no reason to do that anyway. And on the flip side, you can replace the `__add__` attribute of the class and have it used automatically; it was not set in stone when the class was created.

I'll grant you that the `match` construct is definitely not my favourite piece of language design.


> methods are just attributes that are looked up at runtime

At runtime when evaluating a + b no dunder method is looked up and there is no guarantee that a + b === a.__anydunder__(b) https://youtu.be/qCGofLIzX6g

What i mean with weird scoping is

    def foo():
      e = 'defined'
      try:
        raise ValueError
      except Exception as e:
        print(e)
      print(e) # this will error out

    foo()
I also dislike how local/global scopes work in python but that is more of a personal preference.

I agree that that Javascripts standard library is horrible the jsdate.wtf is an extreme but apt example, IMO most of these are solved with some "defensive programming" but I respect other opinions here.

> And no, nobody is IMX actually simply complaining about NaNs existing

I watched many Javascript WTF! videos on youtube and NaNs and [2] == "2" were usually 90% of the content.


Anyway actually my biggest gripe with python is that i find the module/impor/export system counterintuitive


> Oddly enough

It's not that odd, since it's the only situation where you cannot keep it bounded, unless you enjoy having variables that may or may not be defined (Heisenberg variable?), depending on whether the exception has been raised or not?

Compare with the if statement, where the variable in the expression being tested will necessarily be defined.


> Compare with the if statement, where the variable in the expression being tested will necessarily be defined.

    if False:
        x = 7
    print(x)

    print(x)
          ^
    NameError: name 'x' is not defined
Ruby does this sort of stuff, where a variable is defined more or less lexically (nil by default). Python doesn't do this. You can have local variables that only maybe exist in Python.


While somewhat true, what would this be bound to?

    for i in range(0):
        pass


Well, after writing my comment, I realized that a python interpreter could define the variable and set it to None between the guarded block and the except block, and implicitly assign it to the raised exception right before evaluating the except block, when the exception as been raised. So technically, it would be possible to define the variable e in GP example and have it scoped to "whatever is after the guarded block", just like what is done with for blocks.

Is there any chance this would cause trouble though? Furthermore, what would be the need of having this variable accessible after the except block? In the case of a for block, it could be interesting to know at which point the for block was "passed".

So, maybe "None" answers your question?


The answer is: it is unbound. Intellisense will most likely tell you it is `Unbound | <type>` when you try to use the value from a for loop. Would it be possible that it could be default initialized to `None`? Sure, but `None` is a destinctivly different value than a still unbound variable and may result in different handling.


Are you saying that this should result in a name error?

   if <true comparison here>:
       x = 5
   print(x)  # <- should give name error?


I stand corrected, the exception case is definitely an oddity, both as being an outlier and as a strange behaviour wrt Python's semantics. Or is it a strange behaviour?

In the case of an if like in your example, no provision is made about the existence of x. It could have been defined earlier, and this line would simply update its value.

Your example:

   if True:
       x = 5
   print(x)  # 5

Same with x defined prior:

   x = 1
   if False:
       x = 5
   print(x)  # 1
What about this one?

   if False:
       x = 5
   print(x)  # ???


On the other hand, the notation "<exception value> as <name>" looks like it introduces a new name; what if that name already existed before? Should it just replace the content of the variable? Why the "as" keyword then? Why not something like "except <name> = <exception value>" or the walrus operator?

While investigating this question, I tried the following:

    x = 3
    try:
        raise Exception()
    except Exception as x:
        pass
    print(x)  # <- what should that print?


In any sane language it would, yes.


Heisenbug is the word you are looking but may not find.


I may be rusty, but wasn't there a "finally" scope for those situations?

edit: writing from phone on couch and the laptop... looks far, far away...


> `for i in range(5): ...` will leave `i` bound to 4 after the loop. reply

This "feature" was responsible for one of the worst security issues I've seen in my career. I love Python, but the scope leakage is a mess. (And yes, I know it's common in other languages, but that shouldn't excuse it.)


I would love to hear about the security issue if you're able to talk about it


I don't remember the exact details, but it basically involved something along the lines of:

1) Loop through a list of permissions in a for list

2) After the loop block, check if the user had a certain permission. The line of code performing the check was improperly indented and should have failed, but instead succeeded because the last permission from the previous loop was still in scope.

Fortunately there was no real impact because it only affected users within the same company, but it was still pretty bad.


Oof that's a near miss. That's the sort of hard-to-find issue that keeps me up at night. Although maybe these days some ai tool would be able to pick them up


I find it incredibly intuitive and useful that it does that. sometimes it drives me nuts that it doesn't do it for comprehensions but I can see why.

But if something fails in a loop running in the repl or jupyter I already have access to the variables.

If I want to do something with a loop of data that is roughly the same shape, I already have access to one of the the items at the end.

Short circuiting/breaking out of a loop early doesn't require an extra assignment.

I really can't see the downside.


Python 2 actually did let comprehension variables leak out into the surrounding scope. They changed it for Python 3, presumably because it was too surprising to overwrite an existing variable with a comprehension variable.


Oh wow, maybe that's why I expect it to work that way! I can't believe it's been long enough since I used 2 that I'm forgetting it's quirks.


That almost sounds like having the "variables" eax, ebx, ecx, and edx.


Oh yeah, that's a good point.

Python really is a bit of a mess haha.


I cannot tell you how many times I've hit issues debugging and it was something like this. "You should know better" -- I know, I know, but I still snag on this occasionally.


It would be utterly nuts otherwise. For loops over all elements in a sequence. If the sequence is a list of str, as an example, what would the «item after the last item» be?


the issue isn't the value of i, the issue is that i is still available after the loop ends. in most other languages, if it was instantiated by the for-each loop, it'd die with the for-each loop


Maybe Python will get a let one day


There's no block scope in Python. The smallest scope is function. Comprehension variables don't leak out, though, which causes some weird situations:

    >>> s = "abc"
    >>> [x:=y for y in s]
    ['a', 'b', 'c']
    
    >>> x
    'c'
    
    >>> y
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    NameError: name 'y' is not defined
Comprehensions have their own local scope for their local variables, but the walrus operator reaches up to the innermost "assignable" scope.


This is just Pythons scoping, which is not restricted by block, but function. You have the same effect with every other element.


Wow. I had been writing Python for 15 years and I didn't even know that operator exists


It's only existed for 6 of those years so perhaps you can be forgiven :)

The last time I wrote Python in a job interview, one of the interviewers said "wait, I don't know Python very well but isn't this kinda an old style?" Yes, guilty. My Python dates me.


That's literally the first sentence of the article.


Even better is when Standard Ebooks publishes a version: https://standardebooks.org/ebooks/niccolo-machiavelli/discou...


Is there a reason that you don't use YouTube Music for this?


Yeah, nothing makes me go to YouTube Music. Usually, if I'm listening to music on YouTube, it's because a YouTube video of a song came up in a search. If I was on YouTube already, then I had just used the search bar there. If I wasn't, the search engine wouldn't send me to YouTube Music. For music in general, I just use Spotify.

I can't be that weird about using music on YouTube rather than YouTube Music, the post shows someone doing the same thing.


Sorry, didn't mean to imply that you're weird, I was just wondering.


They're asking about viewing existing PRs, not creating new ones.

No need to be so hostile.


https://about.google/belonging/diversity-annual-report/2023/

In 2023, 31.7% of the workforce was white males (page 15).


i dont want to contribute to crying over the difficulties of white men, but the more honest stat would be what percent of the hiring in 2023/2024 was white men

https://static.googleusercontent.com/media/about.google/en//...

the hiring of white people is about the same, and the hiring of men is actually a little bit higher between 2022 and 2023

the interesting take-away here is mostly that there is an increase of hiring of people who are asian while people who are black or latinx are in decline


No worries, you make a good point. Thanks for the assist.


I've read a few books from Hesse, including The Glass Bead Game, and found the English translations rather readable. His more commonly recommended books, Siddhartha and Steppenwolf, should be fine for any high school level reader.


I read it this year, too. It's a fun read, but I wouldn't recommend anything past the first group of articles (that is, don't bother with "Five Five Five Five Five"). The ideas are good, to be sure, but the overall arc past that is pretty weak.


If you enjoyed that, the short stories are quite good. qntm = Sam Hughes, and some of their work is published under that name.


Sam Hughes is a man. Why are you referring to him as their?


If I don’t know someone’s gender and can’t be bothered to look it up I’ll use “they”. And I know Sam’s of both genders.


There's nothing grammatically incorrect or ambiguous about the sentence. What's causing your confusion?


I no idea who Sam is, but I believe "their" is typically utilized to describe plurals while "his", "hers", "its" describe the singular.

My initial reading led me to believe that qntm was a group aliased as Sam.


It’s ideological. It’s using language that intentionally provides less information.


Their usage of "their" aligns with how English has been used for centuries (Wikipedia says 14th century), but more importantly the author's writing was the topic of discussion not their gender.

Policing other's pronoun usage is ideological, but that's your argument, not theirs.


Obviously, that is: statistically, all involved here (the SCP author, the HN commenters, you, me) are men, so saying "he" is very likely correct. If by chance someone here is nonetheless a woman she will probably speak up.


'Their' is practical not ideological - Sam could be Samuel or Samantha, and I didn't know which. Also, bring up the use of 'their' for unknown gender with Shakespeare and Austen, who both did it.

The only one being 'ideological' here is you, getting worked up over basic grammar that's been around longer than Modern English. Go out and touch some grass.


Sam can be short for Samantha or Samuel. "Their" allows one to avoid mis-gendering someone when in ignorance of their gender.


Yeah, the first half or so is a blast, but there’s a point where I feel it drops off quite a bit. (For me, I think it was when the POV changed to Adam.) Still worth a read, though!


HN has a super bland and anti-culture culture. Combine that with the tendency to love technology and watching the free market "solve" "problems" and you're bound to find prolific posters like the parent commenter with these cold takes.

I'm not surprised in the least.


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