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WTFPython – Understanding Python through surprising snippets

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Re: WTFPython – Understanding Python through surprising snippets

#11

Post by yoloClin »

NotSammyHagar wrote: post #5

If only it had curly braces instead of just indention. God, that kills me. And used unicode instead of ascii as the default. And there wasn't python 2.7 vs 3. Someone help me stop this list.

I've coded in python for >10 years and C# for ~half of that. I prefer indentation-based control flow purely because it condenses code vertically and creates consistent indentation with actual purpose (many of the devs on C# projects I've dealt with have had inconsistent tab/space settings and no linting).

If anything, the one thing I hate about Python3 is dynamic typing - inferring datatypes in function bodies is great but strongly typed (and _enforced_) parameters and return values would clean up a lot of the problems I have seen, and created in the past.

Re: WTFPython – Understanding Python through surprising snippets

#12

Post by Erlich_Bachman »

baq wrote: post #7
NotSammyHagar wrote: post #5

If only it had curly braces instead of just indention. God, that kills me. And used unicode instead of ascii as the default. And there wasn't python 2.7 vs 3. Someone help me stop this list.

1. forget python 2.7 exists 2. can't help with the whitespace, sorry; also take care handling Makefiles

> 1. forget python 2.7 exists

But it doesn't work this way. You don't work strictly with the language itself, you work with the whole ecosystem. Libraries, tools, snippets, SO questions, etc. And many of those are still in 2.7 or at least need to specify different solutions for 2.7... It is still a pain.

Re: WTFPython – Understanding Python through surprising snippets

#13

Post by varelaz »

jakear wrote: post #8

My biggest complaint about Python is that it somehow doesn’t get flak for having the same (if not worse) scoping as JS, which gets endless hate for its function-scoped variables. (So much so that block scoped variables are the new normal in JS, but not in Py!) Take for instance: >>> powers_of_x = [lambda x: x^i for i in range(10)] >>> [f(2) for f in powers_of_x] [512, 512, 512, 512, 512, 512, 512, 512, 512, 512] To m…

There is nothing bad in general with list comprehension there. Problem is lambda which uses variable from outer scope. In Python, comparing to JS, using variables from outer scope is not so common. I prefer more obvious constructions and in case of problems with scope I can even create class to protect value that I need to manage.

Re: WTFPython – Understanding Python through surprising snippets

#14

Post by heinrich5991 »

NotSammyHagar wrote: post #5

If only it had curly braces instead of just indention. God, that kills me. And used unicode instead of ascii as the default. And there wasn't python 2.7 vs 3. Someone help me stop this list.

UTF-8 is the current default.

Re: WTFPython – Understanding Python through surprising snippets

#15

Post by avip »

baq wrote: post #6

the first really wtf thing on there is https://github.com/satwikkansal/wtfpython/blob/master/README... where both effect and exception happen; up to that point it's business as usual with garden variety corner cases or implementation details.

I find the explanation lacking? sort also "changes the list in-place", but you can do ([3, 1, 2],)[0].sort()

Re: WTFPython – Understanding Python through surprising snippets

#16

Post by varelaz »

FartyMcFarter wrote: post #9
kraf wrote: post #4

Maybe "beautifully designed" is a bit much then In my experience Python is not very nice to work with. I do like the ecosystem for data science though, it's just amazing how much there is. Hopefully the language will grow into something better now that the dictator stepped down.

Fixings a lot of the WTFs requires breaking backwards compatibility. Given how long it took to transition to Python 3 and how painful the transition was, I'm not sure people will have the appetite or patience for this anytime soon.

A lot of them worked that way or similar in Python 2 and basically they are not a bugs, but optimization or just language design decision.

Re: WTFPython – Understanding Python through surprising snippets

#17

Post by BiteCode_dev »

jakear wrote: post #8

My biggest complaint about Python is that it somehow doesn’t get flak for having the same (if not worse) scoping as JS, which gets endless hate for its function-scoped variables. (So much so that block scoped variables are the new normal in JS, but not in Py!) Take for instance: >>> powers_of_x = [lambda x: x^i for i in range(10)] >>> [f(2) for f in powers_of_x] [512, 512, 512, 512, 512, 512, 512, 512, 512, 512] To m…

I agree totally with that, it's an ugly trap in python, although mitigated by the fact the language doesn't encourage this kind of paradigm so you rarely encounter it.

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.

Re: WTFPython – Understanding Python through surprising snippets

#18

Post by aidos »

jakear wrote: post #8

My biggest complaint about Python is that it somehow doesn’t get flak for having the same (if not worse) scoping as JS, which gets endless hate for its function-scoped variables. (So much so that block scoped variables are the new normal in JS, but not in Py!) Take for instance: >>> powers_of_x = [lambda x: x^i for i in range(10)] >>> [f(2) for f in powers_of_x] [512, 512, 512, 512, 512, 512, 512, 512, 512, 512] To m…

Maybe I’m misunderstanding, but I’d argue that arrow syntax in js is equally special syntax as lambda function. They’re both native ways of making anonymous functions. Python’s version is more clunky, but no more special

Re: WTFPython – Understanding Python through surprising snippets

#19

Post by MaulingMonkey »

baq wrote: post #7
NotSammyHagar wrote: post #5

If only it had curly braces instead of just indention. God, that kills me. And used unicode instead of ascii as the default. And there wasn't python 2.7 vs 3. Someone help me stop this list.

1. forget python 2.7 exists 2. can't help with the whitespace, sorry; also take care handling Makefiles

Maya is still embedding Python 2.x. Soon (tm)...

Makefiles are half the reason I enable visible whitespace in my editors.

Re: WTFPython – Understanding Python through surprising snippets

#20

Post by bakery2k »

baq wrote: post #6

the first really wtf thing on there is https://github.com/satwikkansal/wtfpython/blob/master/README... where both effect and exception happen; up to that point it's business as usual with garden variety corner cases or implementation details.

"Effect and exception" is bad, but its a special case of a more general bad design - the fact that `a += b` is sometimes equivalent to `a = a + b` and sometimes changes in-place.
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