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5% of 666 Python repos had comma typo bugs (inc V8, TensorFlow and PyTorch)

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Re: 5% of 666 Python repos had comma typo bugs (inc V8, TensorFlow and PyTorch)

#241

Post by tyingq »

aylmao wrote: post #99
aeturnum wrote: post #87

The high-level goals of python end up creating these little syntactic landmines that can get even experienced coders. My personal nomination for the worst one of these is that having a comma after a single value often (depending on the surrounding syntax) creates a tuple. It's easy to miss and creates maddening errors where nothing works how you expect. I've moved away from working in Python in general, but I think t…

The lack of a static type-system is IMO what makes these one-character mistakes very annoying. The compiler can't tell you something is wrong, so you're just left to figure out why things are broken, just to realize it was the smallest of typos.

C lets me do this, and doesn't say much about it.

  char ch_arr[3][10] = {
      "uno",
      "dos" 
      "tres"
  };

Re: 5% of 666 Python repos had comma typo bugs (inc V8, TensorFlow and PyTorch)

#242

Post by kazinator »

tgv wrote: post #225
kazinator wrote: post #71

Earlier quoted context omitted.

It is positively not illegal in any standard verision of C since ANSI C 89. It's an essential feature used in all sorts of everyday code. C99 added printf conversion specifiers that are hidden behind macros, and idomatic usage of them relies on string catenation. uint32_t x = 0; printf("x = " PRIx32 "\n", x); where PRIx32 might expand to "%lx" (if uint32_t is the same as unsigned long in that compiler). All sorts of…

I know that. I meant that “abc” + “def” is most likely illegal (although “abc” + ‘d’ is not).

You started talking about "adding strings" in a thread about adjacent literals, without mentioning any + operator..

String catenation ("adding") by adjacency (no visible operator) is a thing; "add" doesn't imply that we are talking about a + operator:

  $ awk 'BEGIN { x = "abc-" 2 + 2 "-def"; print x}'
  abc-4-def

Re: 5% of 666 Python repos had comma typo bugs (inc V8, TensorFlow and PyTorch)

#243

Post by luhn »

aeturnum wrote: post #87

The high-level goals of python end up creating these little syntactic landmines that can get even experienced coders. My personal nomination for the worst one of these is that having a comma after a single value often (depending on the surrounding syntax) creates a tuple. It's easy to miss and creates maddening errors where nothing works how you expect. I've moved away from working in Python in general, but I think t…

I feel like it's been pretty clear from day one that type hints are meant for static analysis with tools like mypy. It's not exclusive to that use and has a lot of other possible applications, but the primary goal has always static analysis.

Re: 5% of 666 Python repos had comma typo bugs (inc V8, TensorFlow and PyTorch)

#244

Post by hibrass »

egeozcan wrote: post #141
jstx1 wrote: post #30

Earlier quoted context omitted.

I mean the zen being wrong is kind of a meme at this point. The whole “only one obvious way to do it” isn’t just false but the exact opposite is true. Python is one of the most flexible languages with many many ways to do the same thing; more than any other language I can think of.

> Complex is better than complicated What? Something being complex is artificial, we try to avoid it. Problems can be complicated, we try to simplify them, and more complicated the problem is, we tend to develop more complex solutions. So comparing them does not make sense? Or did I always know them wrong?

I first encountered the notion of complex/complicated in Antifragile I believe, and IIRC it's based on the [Cynefin framework](https://en.wikipedia.org/wiki/Cynefin_framework).

My understanding is that: * Complex domains lend themselves to experimentation and emergent behavior. * Complicated domains lend themselves to analysis, expertise, and rule following.

The Wikipedia article offers the domains as containing "unknown unknowns" and "known unknowns" respectively.

I'm trying to think how this maps to Python -- the language is complicated, while the problems we're solving are expected to be complex? Or, maybe, the language lives at the boundary between complicated and complex. We push complicated procedures into the language, and let the programmers deal with complex issues?

Re: 5% of 666 Python repos had comma typo bugs (inc V8, TensorFlow and PyTorch)

#246

Post by Someone »

kazinator wrote: post #184
Someone wrote: post #128

Earlier quoted context omitted.

You mean long %s stringnicely breaks upwith indentation and all" ? In my experience, this always gets ugly when you want to insert spaces (= about always). Do you put them at the end or at the start of each string (apart from the first or last string) I think scala’s mkString ( https://superruzafa.github.io/visual-scala-reference/mkStrin... ) is the best solution, visually, for such things, but unfortunately, it woul…

The spaces aren't the point of the comment; rather that we can break the literal into pieces and indent those pieces without affecting the contents. In a non-strawman real exmaple with real data, of course we include all the necessary spaces in the literals. However, this bug is easy to make in C; I've seen it numerous times.

That’s preciseLy my point. This looks nice, but it’s too easy to forget tone of those spaces and to hard to spot that.

Re: 5% of 666 Python repos had comma typo bugs (inc V8, TensorFlow and PyTorch)

#248

Post by jstx1 »

jrockway wrote: post #229
pmarreck wrote: post #212

Earlier quoted context omitted.

Except exit. I knew Python wasn't for me in my first foray into it when I fired its REPL and then went to exit it with control-C or whatever and it literally printed out the right way to do it but then didn't do it. Python was more interested in having me do things a certain way even when it knew what I intended to do, just to be a twit .

The REPL prints the value of a variable that you type in. exit is a variable, and so the REPL prints its value. If you want to run it as a function, you can do that, and indeed its string value is a message telling you to do that. $ python3 Python 3.9.2 (default, Feb 28 2021, 17:03:44) [GCC 10.2.1 20210110] on linux Type "help", "copyright", "credits" or "license" for more information. >>> exit Use exit() or Ctrl-D (…

ipython has 'exit' without the parentheses.

Re: 5% of 666 Python repos had comma typo bugs (inc V8, TensorFlow and PyTorch)

#249

Post by dannymi »

I can see the value of a lint (if there's a newline without a comma, warn), but concatenating strings by multiplication is the correct thing to do (since it's also used this way in mathematics of parsers).

Using the plus operator to concatenate strings is just weird.

Think of the usual algebraic properties these operators are supposed to have.

"+" always is supposed to be commutative--so "a"+"b" = "b"+"a", if those mean alternatives (they usually do mean that in mathematics), is just fine.

On the other hand, multiplication is often not commutative--also not here. "a" "b" != "b" "a".

So string concatenation should be the latter. And indeed that's how it's in regular expression mathematics for example.

Re: 5% of 666 Python repos had comma typo bugs (inc V8, TensorFlow and PyTorch)

#250

Post by housecarpenter »

nojs wrote: post #201
oa2022 wrote: post #41

Earlier quoted context omitted.

This change would break a lot of legacy code for no good reason The most common way to split a string in lines is using this concatenation formula.

> The most common way to split a string in lines is using this concatenation formula. Is it really? I tend to avoid it in favour of ””” or ‘\n’.join( ), because it looks like a mistake. Triple quotes are kind of annoying if the string is indented, but you can just not indent the string to avoid the whitespace.

I use it, personally. The other two options I find too aesthetically displeasing: not indenting the string looks bad when it's within an indented block of code, and using join and putting the strings in a list is just too much boilerplate. I will use """ if I don't care about the extra space put at the start of each line by the indentation.
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