Hacker News Reader

Comment by brudgers | Hacker News Reader

The worst idiom of Python is the idea of Pythonic. It is usually prefixed with "un" and used pejoratively. The rest of the cases it is used to rationalize arbitrary biases such as Python's lack of an identity function and the removal of map and filter [1] from the core language.

There's no such thing as "very Pythonic." It's a binary and the worst aspect of Pythonic is that people waste so much energy trying not to be unPythonic in order to meet the mores of the community.

[1]: Edit, Ok, I was confusing two experiences. It was reduce's removal that broke my code using the map->filter->reduce idiom. Map broke by returning a Map object rather than a list (but that was between Python and Python3). And so far as I know, filter has not been changed so as to break code.

View on HN

> the worst aspect of Pythonic is that people waste so much energy trying not to be unPythonic in order to meet the mores of the community

This is why Python is so successful, and yet you've never heard anything about "Python fatigue." Being "Pythonic" (which as a proxy I will define as not needlessly flouting the principles that `python -mthis` prints out) is valued by most open source projects and most heavy Python users.

With respect to your complaints, they are not "arbitrary biases," they are all the same conscious decision on the part of Guido to favor the use of comprehension syntax over higher-order functions. See https://www.artima.com/weblogs/viewpost.jsp?thread=98196

You might disagree with that decision and prefer another language, but it is not arbitrary at all.

I do minimal python programming but your comment made me re-read The Zen of Python. Such a good reminder of what I'd definitely call good practices.

The analogy of religion at its core is part of what makes Pythonic such a toxic concept. It provides the Python community an excuse to treat being unPythonic as moral failing and PEP's as revelation.

I suppose a true believer could look at double snake case as a convention to denote private methods in lieu of implementing modular code with actual private methods and see something beautiful and simple and explicit and uncomplicated and a good practice. There's nothing wrong with Python except the bullshit that surrounds it.

I attribute most of Python's growth to being a better general purpose lanaguage than MatLab and BASIC and Java and C++ and FORTRAN in common academic settings and more readable than Perl and more robust than TCL for moderate sized systems in commercial settings. Given JavaScript, there is evidence that the arbitrariness of a programming language's design is at best weakly correlated to its adoption.

But we're not talking about the language per se; we're talking about the library and application developers and the influence that the notion of "Pythonic" has on them.

Imagine there wasn't such a unifying straw man concept or platonic ideal of being good Python. Would there still be single NumPy and SciPy implementations? Or would the work be scattered across smaller, less well-resourced efforts whose contributors disagreed on ultimately trivial things like whether the API makes use of higher-order functions, metaprogramming, or having many ways to do something?

There's no Pythonic analog in JavaScript and there are still many useful libraries and applications. There's the entirely orthogonal MINSWAN in Ruby and yet there's Rails. On the numeric side, there's Boost in Cpp and BLAS in Fortran. And NumPy is useful because of the development using C where Pythonic is irrelevant.

> There's no Pythonic analog in JavaScript and there are still many useful libraries and applications.

Yes, that's exactly my point, there are many of them, none of which really have the same sort of universal buy-in, because people are constantly disagreeing about .forEach vs. for loops, or promises vs. callbacks, or whatever.

Boost has very strict guidelines about its approach to design and implementation[1] -- it even quotes the Zen of Python.

I didn't say that the concept of "Pythonic" is necessary to implement high-performing and widely-used libraries. I am merely contradicting your unsubstantiated assertion that the concept is harmful.

[1]: http://www.boost.org/development/requirements.html

I understand why you would feel this way but I disagree. The meme of being pythonic has the benefit of most libraries being understandable. It is always very obvious when python code has been written by someone who specializes in another language, and it is usually painful to read their code.

So if I have this right, things like Django's Class Based Views and sqlalchemy are Understandable. I'll take functional-style python over Understandable python any day of the week.

Yes, they're both very understandable. Sorry about your mental blocks.

I love Django's classed based views, though I could see how they would be annoying if you aren't steeped in Python's multiple inheritance.

Granted, If it weren't for Pycharm's command+click to open up where an object was defined I don't think I would like them quite as much. But being able to quickly walk the inheritance path, and finding simple clear code in small chunks is very nice.

I would say those two examples are not very Pythonic because they are overly abstracted.

Like I said, the usual use of the 'Pythonic' idiom within the Python community is prefixed by "un" and used pejoratively. One aspect of the perniciousness of 'Pythonic' is that it promotes the tribalist ideal of specializing in languages. For someone optimizing for readable libraries, Smalltalk is probably a better option.

Your comments are making me bristle a little bit, but to be honest the book being referenced by the blog post makes me bristle more.

"You may use the “harmful” examples as templates to search for in your own code. When you find code like that, replace it with the idiomatic version."

This is a really dumb idea, especially when paired with the incorrect implementations that the book author encourages and the blog poster critiques.

Incorrect code is never idiomatic, full stop.

Incorrect code is incorrect code. Correct code is useful in and of itself. Idiomatic code isn't.

> the removal of map and filter from the core language

This never happened-- perhaps you're thinking of reduce? And reduce is still in it, it just got moved to `functools`.

Hah, I didn't even know that it never happened. Goes to show the relative utility of map/filter vs comprehensions...

It was proposed to do that with all three, and they walked it back to just reduce because there was a huge outcry.

Thanks, I stand corrected. My high level memory is that the map->filter->reduce idiom was broken because <arbitrary>. Adding to my confusion was my conflating that <arbitary> with my memory of map breaking code by returning a map object rather than a list.

You're right in that map returned a list in python 2, but in python 3, it returns an iterator. Anyone who relied on indexing or non-lazy behavior would have their code break.

GVR doesn't like functional-style programming, so he much prefers the iterative but compact comprehension alternatives.

It may just be the circles I hang out in, but most folks aren't map/filter versus comprehension purists. I'll do comprehensions usually, but map/filter when it helps make the line shorter or more readable.

I don't have anything against list comprehensions. Sometimes they are a very useful abstraction. Other times map->filter->reduce better expresses the business logic of the program (e.g. when the analog is signal processing [1] or Unix pipes).

My issue with 'Pythonic' is that it is used to express the idea that someone's thoughts are or are not properly structured.

[1]: https://mitpress.mit.edu/sicp/full-text/sicp/book/node35.htm...

Most of it ok, but the notion of truthiness and falsiness being pythonic (or even allowed!) was python's billion dollar mistake.

It's a magnet for bugs (e.g. stock items with a price of zero being treated as items with no price at all).

Please don't ever write Python programs with this mentality.

Like I said, Pythonic defaults to pejorative.

Reply on news.ycombinator.com