all these cool new features! what's the thing they always say about python? "there's more than one way to do it"?
That's a Perl slogan but I suspect you already knew that
WTF Python: Exploring and understanding Python through surprising snippets
21–30 of 169 posts
Re: WTF Python: Exploring and understanding Python through surprising snippets
#22I feel like WTFs caused by doing something deeply weird hardly counts against the language. Yes doing the walrus operator inside brackets works. Yes of course it's going to be doing weird things. Is this really surprising to anyone? It's not what that operator is for . Yes comparing strings with "is" works sometimes . It's not checking equality and it isn't supposed to. In another implementation using "is" might work…
> I've been seeing a growing anti-python sentiment lately
The same happened to Ruby and Rails. Once the last "in" thing no longer gets attention and new "in" things are the talk of the blogosphere, "yesterday's" things start to get dissed.
I think it's to gain points for recognizing the new thing. To attract people following "old" thing to the "new" thing and provide social validation or increased mindshare for one's choices.
Or maybe people are tired of pain points with the old way (even if just perceived or tangentially related), and they need to lash out at something.
Re: WTF Python: Exploring and understanding Python through surprising snippets
#23I feel like WTFs caused by doing something deeply weird hardly counts against the language. Yes doing the walrus operator inside brackets works. Yes of course it's going to be doing weird things. Is this really surprising to anyone? It's not what that operator is for . Yes comparing strings with "is" works sometimes . It's not checking equality and it isn't supposed to. In another implementation using "is" might work…
Serious question: how do you know how the language is intended to be used?(or what the one right way is). Last time I checked, I couldn't find a document about this.
Most likely by interacting with other python developers once you run into trouble doing things in odd ways. Same as for any other language.
Main difference is that the python community has a rather strong reaction to how pythonic your code is. You'll notice soon enough after working with python that for most python developers "it works" isn't good enough reason for anything. It has to work and fit how you're supposed to write python.
Some of it is encoded in style guides like pep8, but most of it is pretty hard to codify like that.
Re: WTF Python: Exploring and understanding Python through surprising snippets
#24Ah, brings to my mind the classic talk: https://www.destroyallsoftware.com/talks/wat
That one was all cynicism that baited the experienced and confused and discouraged beginners... this one actually takes the important next step of making it all teachable which is really great.
Oh no, someone was being funny! Think of the beginners, they can't deal with that!
The wat talk is funny and educational. I watched it with just a couple of weeks of experience in JavaScript, and I learned a lot from it. There are other great resources (the good parts, the you don't know js series, etc), but none of them offer value so quickly.
The wat talk is a great reminder to learn more about the language you are using and start reading the aforementioned books.
Re: WTF Python: Exploring and understanding Python through surprising snippets
#25I feel like WTFs caused by doing something deeply weird hardly counts against the language. Yes doing the walrus operator inside brackets works. Yes of course it's going to be doing weird things. Is this really surprising to anyone? It's not what that operator is for . Yes comparing strings with "is" works sometimes . It's not checking equality and it isn't supposed to. In another implementation using "is" might work…
I agree with most of your points, because in most cases, people try something very weird, and they are surprised that the result is something even weirder (or they just didn't think through the example logically). Except the string comparison with "is". It's confusing, because there are no errors, and when I try them in the Python REPL, it "works". The code is logical, I tested the example and it works... ...except w…
The confusion there is caused by english not disambiguating between equality and being-the-exact-same-thing-ness. I'll grant that "is" is a bit of a footgun for new users, but it's not a WTF in the sense that the language is doing something weird.
Rule of thumb is use == for everything except True/False/None. Once you get going with python you'll learn the meaning of is eventually, and you'll still barely ever need to use it.
Re: WTF Python: Exploring and understanding Python through surprising snippets
#26Earlier quoted context omitted.
> I've been seeing a growing anti-python sentiment lately Despite the name, I don't think this is anti-python, in the same way classics like [0] are anti-PHP. The project README mentions this a bit: > While some of the examples you see below may not be WTFs in the truest sense, but they'll reveal some of the interesting parts of Python that you might be unaware of. I find it a nice way to learn the internals of a pro…
Fair enough I suppose, but I'm still seeing posts like the OP getting linked all over the place by people trying to disparage python as a language. Of course once you get more deeply into a language it's probably a really good thing to get to know all the weird edge cases. One of my favorite past-times is writing intentionally terrible code just to exercise some of those edge cases. For instance this hello world code…
this is the same defense against the php and javascript posts: if you know the entire language really well none of these are actually problems
Re: WTF Python: Exploring and understanding Python through surprising snippets
#27>>> another_tuple ([1, 2], [3, 4], [5, 6, 1000]) >>> another_tuple[2] += [99, 999] TypeError: 'tuple' object does not support item assignment >>> another_tuple ([1, 2], [3, 4], [5, 6, 1000, 99, 999]) This one's my favorite. Although it's a rare issue that you're unlikely to come across, it's a side-effect of a much bigger design flaw in Python - the decision to make `a += b` behave differently from `a = a + b`.
That's a wart and a half. It puzzles me to no end that this would be an error - `another_tuple[0].append(3)` is not an error.
Re: WTF Python: Exploring and understanding Python through surprising snippets
#28While this repo is great for education, it doesn't cover the deep problems with Python that you only discover when you try to do something "unapproved" or slightly off the happy path. Depending on the domain you are working in you may never encounter such a situation, but if you do, be prepared to lose your sanity one omnipresent design flaw at a time.
Over the years I've been collecting a series of cases that are somewhat more nihilistic and depressing under the general category of LOL PYTHON. The little inconsistencies, the boilerplate that is required if you don't want to use only the approved, not performant, and breaks all sorts of other hidden assumptions so you can't actually use the code outside very narrow settings approach, eventually just evoke a nihilistic chuckle and a note to never start a new Python project again.
Re: WTF Python: Exploring and understanding Python through surprising snippets
#29Earlier quoted context omitted.
Fair enough I suppose, but I'm still seeing posts like the OP getting linked all over the place by people trying to disparage python as a language. Of course once you get more deeply into a language it's probably a really good thing to get to know all the weird edge cases. One of my favorite past-times is writing intentionally terrible code just to exercise some of those edge cases. For instance this hello world code…
this is the same defense against the php and javascript posts: if you know the entire language really well none of these are actually problems
If you'll read more carefully you'll find that that's not what I said. I said none of these are problems you'll run into. Even as a newcomer.
Once you're getting better at the language it's nice to know these edge cases because they teach you details about the language you'd otherwise miss out on.
Re: WTF Python: Exploring and understanding Python through surprising snippets
#30>>> another_tuple ([1, 2], [3, 4], [5, 6, 1000]) >>> another_tuple[2] += [99, 999] TypeError: 'tuple' object does not support item assignment >>> another_tuple ([1, 2], [3, 4], [5, 6, 1000, 99, 999]) This one's my favorite. Although it's a rare issue that you're unlikely to come across, it's a side-effect of a much bigger design flaw in Python - the decision to make `a += b` behave differently from `a = a + b`.
It's a design decision to allow it to behave differently, as you can implement += with a more efficient in-place version, instead of a copying one where the lvalue might be different/new and you have to keep the old a. I even think this is good design, as by convention + does not mutate its arguments but += can be a fast mutating version.
I guess reference counting makes copying a list in Python a much more expensive operation than it would be in other languages. Although perhaps it could also be used to avoid copying in cases where the list's own reference count is exactly 1?
Anyway, there's nothing wrong with offering an operator to change a list in-place, but IMO `+=` is the wrong way to spell it.