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0 pointsdragonwriter7y ago0 comments

> I'd be curious which of JavaScript, perl, js, and Ruby (and hell, go or Java, which are often considered high level) is more friendly to fp than python, and why, obviously.

JS (which you listed twice), Perl (5 or 6), and in some ways Ruby (which is a mixed bag, because it doesn't actually have functions per se, but even so is in many ways more friendly to functional style than Python.)

Being expression-oriented languages with full support for anonymous functions (callables in Ruby) and non-awkward creation of full (rather than read-only) closures are the main common factors.

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joshuamorton7y ago

Sorry, php, not js the second time.

I'm not sure what you mean by read only closures, unless you mean a close which can later modify the enclosing scope, which python supports via the nonlocal keyword but also is decidedly bad, and not something I've ever before heard of as an fp concept.

And as far as I can tell, your entire argument reduces to better lambdas. Which is what you said it wouldn't be. I feel misled. Oh wait you're a different user. Still this point stands. I wouldn't have responded if the expected answer was "better lambdas". You can do better.

I guess the next important question is "what are the things you feel make a language functional, and why are those things valuable"?

There are lots of aspects of functional programming that are good, I personally agree that anonymous functions are not one of them, especially when you have no need for callbacks (python doesn't really).

And it's very possible to write functional code, imo, without anonymous functions. Why do you disagree.

pmontra7y ago

Ruby has multi line lambdas and code blocks. Python doesn't. However we can't pass a function as argument (actually a method but it could be a def in a module). We can pass a symbol with the name of the fuction. We can pass the function in Python.

I write very few classes in Python. I tend to write modules and import them. It's what I do in Elixir, obviously.

However I don't write much Ruby code outside Rails and Rails is definitely object oriented and directs the developer to write OO code. Instead the most popular web framework for Python, Django, is almost anarchy, anything will do.

dragonwriterOP7y ago

> However we can't pass a function as argument

Right, Ruby doesn't have functions at all, so you can't pass them. This is why Ruby isn't simply better than Python here, though I'd say it's still mostly better.

> We can pass a symbol with the name of the fuction.

No, you can either convert the name to a callable and pass that, or for some methods you can pass the name of a method you'd like called on an object that the called method will get somewhere else. This isn’t esuivslent to having the name of a function. Instead, its a facility that is usually offered by a method to provide a more concise alternative to passing an equivalent block for a no-arg method. E.g.:

  enum.inject(start, :foo)

is equivalent to:

  enum.inject(start) { |obj| obj.send(:foo) }

If you actually have a function-like (callable) object (bound method object or proc/lambda) you can send that as a regular argument, or if the method it is passed to expects a block (as is more frequently the case for Ruby methods that need a single function-like argument) convert the callable to a block with the “&” prefix and send that.

steveklabnik7y ago

> No

I think they're referring to Symbol#to_proc.

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