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Why Python is Important for You

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Re: Why Python is Important for You

#171

Post by chromatic »

aangjie wrote: post #104
tete wrote: post #16

I am kinda afraid of getting down voted, but I have used Python and I feel like I get all this and more (CPAN) when using Perl. The major difference in my opinion is that Perl gives you even more freedoms, which causes you to need some self discipline, but you get stuff done even quicker that way. It feels a bit like Python is better for programming beginners or people that tend to be too lazy sometimes and Perl is f…

Ok, just as a disclaimer: i recently read Larry Wall's post on perl design principles +natural language and am reconsidering perl.. But honestly all my previous experience poking around with perl have been horrible... it's pretty messed up syntax to read... i guess it may not be so hard for a perl expert..

Most Perl tutorials do a terrible job of explaining the two or three things you really need to understand to learn Perl syntax. I wrote Modern Perl to rectify that:

http://onyxneon.com/books/modern_perl/

Re: Why Python is Important for You

#172

Post by rue »

evincarofautumn wrote: post #92
pranjalv123 wrote: post #22

My biggest problem with Python is that projects larger than a given size tend to become unmaintainable rather quickly. This is in large part because of the lack of strong typing and type annotations; if you aren't the only author or can't keep the codebase in your head, it takes real effort to figure out what a function does. Even the type annotations provided in a language like Java or C++ make this task much easier…

This is a significant problem for me as well, coming from C++ and Haskell. Even just going through and making a few changes here and there, there’s no way for me to know without extensive testing whether my edit was even remotely correct beyond a cursory syntax check. I’ve never had to deal with testing all that heavily in statically typed languages, because I can rely on the type system to do a lot of very helpful s…

> I’ve never had to deal with testing all that heavily in statically typed languages,

Lack of tests means bugs now, or later when you're refactoring. They're pretty essential in static languages, too, although you can certainly lean on the compiler for many things.

Anecdotally, my bugs usually aren't caused by having passed in the wrong kind of an object.

Re: Why Python is Important for You

#173

Post by pnathan »

anthonyb wrote: post #149
espeed wrote: post #138

Earlier quoted context omitted.

You think immutable strings is a bad thing?

Yeah, I goggled a bit at that one too. Particularly when it's immediately followed by a complaint about things being modified unexpectedly. Some of the complaints are not really issues, eg. you can comment out loops by adding an "if 0:" after commenting out the top line, or else surrounding it with triple quotes """...""". [5] is an outright lie. Major Python apps support 2.4 onwards, true, but virtualenv (a common p…

Python mixes immutability and mutability in ways that require careful thinking about the problem if you want to write unbuggy code. E.g., does a tuple holding lists allow modification of the member lists? Intuitively, it would seem to me that immutability should cascade, but thinking about tuples as holding a bag of pointers suggests that the lists are still mutable. Anyway.

I generally take the position that if you have to work around something in your language, it's broken. E.g., the virtualenv hack. It's nice to deploy out an exe and not require a whole ecosystem to be install in order to bootstrap it up.

Happy hacking.

Re: Why Python is Important for You

#174

Post by j-kidd »

craigyk wrote: post #158
dcosson wrote: post #80

Earlier quoted context omitted.

Agreed that they can be tricky initially and hard to debug, but I think they're totally worth it for eliminating repetitive code. And IMO as long as there isn't a bug in the decorator itself, code with decorators can be just as readable (if not more so) to someone else (e.g. decorating your functions with @authenticated instead of if self.user.is_authenticated: # blah, blah blah)

if Python had better function syntax and anonynous functions, decorators wouldn't even be a 'thing'

Can you elaborate on that? The more I use Python, the more I find it to be a well thought out language with a very consistent feel, allowing me to write code without thinking. Well, except when it comes to decorators. How would you propose to improve the syntax?

Re: Why Python is Important for You

#175

Post by rue »

wging wrote: post #11

As a commenter on the article wrote: what about Ruby? I say this as a happy Python user. Ruby seems very similar but I'm reminded of a pg essay on language power: looking up the power curve, you see '$Language plus a bit of weird stuff that is probably irrelevant.' So I don't trust myself. As someone who loves Python and doesn't know any Ruby beyond a few bits of syntax and the obvious bits that are common to most la…

> As someone who loves Python and doesn't know any Ruby beyond a few bits of syntax and the obvious bits that are common to most languages, what am I missing?

Nothing. Everyone jokes about turing completeness, but Ruby and Python are pretty much exactly equivalent for their users. Python's got the upper hand in some areas, Ruby in others, but you'll get it done.

If Python works for you, use it. I didn't like it, the object model/runtime never felt right[1]. Ruby's did, it's internally consistent.

[1] The classic len(str), the underscored methods, recently decorators…

Re: Why Python is Important for You

#176

Post by funksta »

chernevik wrote: post #126
wging wrote: post #11

As a commenter on the article wrote: what about Ruby? I say this as a happy Python user. Ruby seems very similar but I'm reminded of a pg essay on language power: looking up the power curve, you see '$Language plus a bit of weird stuff that is probably irrelevant.' So I don't trust myself. As someone who loves Python and doesn't know any Ruby beyond a few bits of syntax and the obvious bits that are common to most la…

Ruby/Rails seems to have a more developer-friendly approach to the web development stack than Python/Django. (I am but an egg, more comfortable in Python/Django but learning Ruby/Rails, I wouldn't argue with more experienced folks about any of the following.) Ruby/Rails seems easier to develop and test the full stack application, from client JavaScript to server Ruby response and back. It supports Ajax through inject…

One of the differences between Django and Rails is that the former makes almost no assumptions about how you are going to write your front end. I don't know much about Rails, but it seems to me that it is much more opinionated in that regard.

Re: Django & Backbone, you should check out djangbone. It makes it dead simple to create a basic backbone-compatible APIs in Django, and is easy to extend if you need more advanced functionality (full disclosure- I'm its author): https://github.com/af/djangbone

Re: Why Python is Important for You

#177

Post by lelele »

niels wrote: post #46
pranjalv123 wrote: post #22

My biggest problem with Python is that projects larger than a given size tend to become unmaintainable rather quickly. This is in large part because of the lack of strong typing and type annotations; if you aren't the only author or can't keep the codebase in your head, it takes real effort to figure out what a function does. Even the type annotations provided in a language like Java or C++ make this task much easier…

Just to be clear, Python is strongly typed but not statically typed. But I definitively agree with your comment. The startup I'm working for is Python based, but I'm currently learning Haskell, because I'd like to take advantage of a good type system for my larger efforts.

Aren't you concerned about unpredictable memory requirements?

Re: Why Python is Important for You

#178

Post by cdavid »

nostrademons wrote: post #68
cdavid wrote: post #62

Earlier quoted context omitted.

On most projects I have seen where python was seen as problematic, I think that having types ala C++/Java would not have improved much. The real problem is that the function is not documented, nor is the function expectations. Typing in C++/java does not replace that (more advanced typing systems do much better, though). Package management and generally deployment is certainly a pain in python. I think it is one of t…

In most C++/Java code, the function is not documented either. The nice thing about manifest types is that the source code becomes the documentation (shitty documentation, yes, but usually good enough that you can figure out how to use it by looking at the source). Type inference with a doc generator would work too, as long as you run the doc generator regularly and everybody knows where to find the docs. History has…

It is not my experience that you can figure out how to call functions correctly just from the function signature. Certainly, that's not true from C++ when you need to figure out lifetime issues, etc… It may be possible to figure out from the source code, if the code is written well enough, but that's true independently of the language IMO. Developer not writing decent doc is an institutional problem, and if this cannot be enforced, then the institution is most likely not capable of producing very good code either.

I think it is more interesting to talk from the POV of how to write code that is actually readable: type may help, but that's only a not that important part of the equation in my experience.

Re: Why Python is Important for You

#179

Post by tikhonj »

craigyk wrote: post #157
bmelton wrote: post #151

Earlier quoted context omitted.

Syntactically, JS is funny in a lot of ways. I highly encourage you to investigate CoffeeScript.

As someone with lots of Python experience, having used CoffeeScript/JS for ~three months makes Python looks somewhat old fashioned when I switch back. If Coffee/JS had some way of overloading array access operations, and maybe a numpy equivalent, I don't think I would have any reason to go back to Python. It's also just so much faster than CPython...

The upcoming version of JavaScript--some engines already support this, I think--includes support for "proxies" which basically let you overload both array access (a['b']) and . access (a.b) for an object.

Re: Why Python is Important for You

#180

Post by cdavid »

evincarofautumn wrote: post #92
pranjalv123 wrote: post #22

My biggest problem with Python is that projects larger than a given size tend to become unmaintainable rather quickly. This is in large part because of the lack of strong typing and type annotations; if you aren't the only author or can't keep the codebase in your head, it takes real effort to figure out what a function does. Even the type annotations provided in a language like Java or C++ make this task much easier…

This is a significant problem for me as well, coming from C++ and Haskell. Even just going through and making a few changes here and there, there’s no way for me to know without extensive testing whether my edit was even remotely correct beyond a cursory syntax check. I’ve never had to deal with testing all that heavily in statically typed languages, because I can rely on the type system to do a lot of very helpful s…

I find the focus on dynamic typing a bit fascinating: you don't see people focus so much on it on a discussion about LISP. [EDIT: I meant to say that this most likely reveals something else is at work in the particular case of python].

When a C program compiles, it really does not tell you much about whether it will work or not. Maybe it is a matter of application domains, but I tend to actually spend more time testing C parts of the code compared to the python code. But, in proportion, I spend more time testing in python than in C, because I spend so much less time doing things in python than in C.

Haskell is different, because types can be used to enforced constraints in a much better fashion than C/C++/Java/etc…

The one part when simple typing systems is useful is refactoring. Doing so in a dynamically typed language is difficult (but possible, as shown by smalltalk, which is supposedly even more dynamic than python).

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