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What's Coming in Python 3.8

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Re: What's Coming in Python 3.8

#161

Post by Sohcahtoa82 »

simondw wrote: post #62
JustSomeNobody wrote: post #47

Earlier quoted context omitted.

I see what you're saying, but I kinda like the gets ":=" operator.

But now there are two ways to do assignment. That's not very pythonic, is it?

I see this criticism every time the walrus operator is brought up.

You do know that this:

    x := 1
Is going to be a syntax error, right? The walrus operator is not permitted in the case of a simple assignment statement. It's only in an expression.

Re: What's Coming in Python 3.8

#162

Post by owlowlowls »

stefco_ wrote: post #146

There's a lot of talk in this thread about Python going down-hill and becoming less obvious/simple. I rather like modern python, but I agree that some features (like async/await, whose implementation fractures functions and libraries into two colors [0]) seem like downgrades in "Pythonicity". That said, I think some things have unquestionably gotten more "Pythonic" with time, and the := operator is one of those. In c…

>I'll add that := fixes something I truly hate: the lack of `do until` in Python, which strikes me as deeply un-Pythonic. Am I supposed to break out of `while True`? Am I supposed to set the variable before and at the tail of the loop (a great way to add subtle typos that won't cause errors)?

This is relevant to what I've been doing in OpenCV with reading frames from videos! In tutorial examples on the web, you'll see exactly the sort of pattern that's outlined in the PEP 572 article.

>line = f.readline()

>while line:

> ... # process line

> line = f.readline()

Just, replace readline() with readframe() and the like. So many off-by-one errors figuring out when exactly to break.

Re: What's Coming in Python 3.8

#163

Post by LaGrange »

voldacar wrote: post #8

Python looks more and more foreign with each release. I'm not sure what happened after 3.3 but it seems like the whole philosophy of "pythonic", emphasizing simplicity, readability and "only one straightforward way to do it" is rapidly disappearing.

In my experience, every technology focused on building a "simple" alternative to a long-established "complex" technology is doomed to discover exactly _why_ the other one became "complex." Also spawn at least five "simple" alternatives.

Doesn't mean nothing good comes out of them, and if it's simplicity that motivates people then eh, I'll take it, but gosh darn the cycle is a bit grating by now.

Re: What's Coming in Python 3.8

#164

Post by pmontra »

sametmax wrote: post #19
stakhanov wrote: post #10

Speaking as someone who has written Python code almost every day for the last 16 years of my life: I'm not happy about this. Some of this stuff seems to me like it's opening the doors for some antipatterns that I'm consistently frustrated about when working with Perl code (that I didn't write myself). I had always been quite happy about the fact that Python didn't have language features to blur the lines between what…

F-strings have appeared 2 versions ago. All in all, the feedback we have has been overwhelmingly positive, including on maintenance and readability.

F-string are great and should have been in the language since the beginning. Many other languages had with their own version of them since version 0. What I don't understand is why Python needs a special string type when other languages can interpolate normal strings (Ruby, Elixir, JavaScript.)

Re: What's Coming in Python 3.8

#165

Post by kbd »

owlowlowls wrote: post #162
stefco_ wrote: post #146

There's a lot of talk in this thread about Python going down-hill and becoming less obvious/simple. I rather like modern python, but I agree that some features (like async/await, whose implementation fractures functions and libraries into two colors [0]) seem like downgrades in "Pythonicity". That said, I think some things have unquestionably gotten more "Pythonic" with time, and the := operator is one of those. In c…

>I'll add that := fixes something I truly hate: the lack of `do until` in Python, which strikes me as deeply un-Pythonic. Am I supposed to break out of `while True`? Am I supposed to set the variable before and at the tail of the loop (a great way to add subtle typos that won't cause errors)? This is relevant to what I've been doing in OpenCV with reading frames from videos! In tutorial examples on the web, you'll se…

For sure. Walrus operator is "unnecessary" but is a clear improvement in the code that will use it.

Re: What's Coming in Python 3.8

#167

Post by president »

Anyone else think the walrus operator is just plain ugly? There is a certain aesthetic quality that I've always appreciated about the Python language and the walrus operator looks like something straight out of Perl or Shell.

Re: What's Coming in Python 3.8

#168

Post by fatbird »

londons_explore wrote: post #70

I long for a language which has a basic featureset, and then "freezes", and no longer adds any more language features. You may continue working on the standard library, optimizing, etc. Just no new language features. In my opinion, someone should be able to learn all of a language in a few days, including every corner case and oddity, and then understand any code. If new language features get added over time, eventua…

All you're doing then is moving the evolution of the language into the common libraries, community conventions, and tooling. Think of JavaScript before ES2015: it had stayed almost unchanged for more than a decade, and as a result, knowing JavaScript meant knowing JS and jQuery, prototype, underscore, various promise libraries, AMD/commonjs/require based module systems, followed by an explosion of "transpiled to vanilla JS" languages like coffeescript. The same happened with C decades earlier: while the core language in K&R C was small and understandable, you really weren't coding C unless you had a pile of libraries and approaches and compiler-specific macros and such.

Python, judged against JS, is almost sedate in its evolution.

It would be nice if a combination of language, libraries, and coding orthodoxy remained stable for more than a few years, but that's just not the technology landscape in which we work. Thanks, Internet.

Re: What's Coming in Python 3.8

#170

Post by girzel »

txcwpalpha wrote: post #71
coldtea wrote: post #30

Earlier quoted context omitted.

> It's not clear to me what it does just from reading it How isn't it entirely obvious? := is the assignment operator in tons of languages, and there's no reason not to have assignment be an expression (as is also the case in many languages).

> := is the assignment operator in tons of languages It is? Which ones? Other than Go, I can not think of a single language that has ":=" as an operator. Java does not, JavaScript does not, C/C++ do not, Ruby does not, I don't think PHP does, Erlang/Elixir do not, Rust does not... (I could be wrong on these, but I've personally never seen it in any of these languages and I can't find any mention of it in these langua…

And Ocaml:

https://ocaml.org/learn/tutorials/structure_of_ocaml_program...

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