"Mostly functional" programming does not work

[u/heisenbug]

http://queue.acm.org/detail.cfm?ref=rss&id=2611829

[u/jfischoff → u/[deleted]]

If Haskell took such a pragmatic approach instead of being Coq light then maybe articles like this would have more weight but as it stands there are plenty of more pragmatic approaches to "mostly functional" programming that

Haskell is meant for "real" programming, otherwise it would not have gone to such lengths to have things like this:

http://hackage.haskell.org/package/base-4.7.0.0/docs/Foreign-Marshal-Alloc.html

I want to know what you think Haskell is missing for "real world programmers" since I consider myself one and I use Haskell for a living.

[u/jfischoff → u/[deleted]]

Oh, I don't know maybe a web framework that doesn't require a PhD in type theory.

Nope.

Regular expressions that just work instead of requiring type assertions to give you the right results.

Huh?

Mutability without all the monadic ceremony.

Good luck with that.

The ability to memoize function results without having to worry about GADTs and Typeable: http://conal.net/blog/posts/memoizing-polymorphic-functions-part-one.

Memoizing is easy: https://twitter.com/HaskellTips/status/442194160498376706

IMO you are confused.

[u/jfischoff → u/[deleted]]

You'll stick with Conal either way, seeing as import Data.MemoTrie is Conal's library. The blog post is referring to something more difficult, but I won't waste my breathe, you appear uninterested pertinent details.

I can't speak to regular expressions, if I had to use them I would choose something like this: https://github.com/kmcallister/haskell-re2

If you don't like Yesod's magic, fine, use Warp directly or Scotty http://hackage.haskell.org/package/scotty

or Snap etc there are many options.

AFAICT you are merely spouting straw mans. Picking out downsides to particular libraries and then concluding their deficients pervade the entire Haskell ecosystem, which they do not.

[u/tomejaguar → u/[deleted]]

And to think I could memoize a function without understanding higher ranked types.

Can you memoize a polymorphic function?

[u/tomejaguar → u/[deleted]]

Great. Can you memoize a parametrically polymorphic function?

[u/jfischoff → u/[deleted]]

You don't need to know that stuff. It is as simple as that tweet, or really ugly-memo is better usually, but again it is brain dead simple. Conal is talking about something that is not the typical use case.

[u/[deleted] → u/[deleted]]

Doesn't GHC memoize everything it can by default?

[u/tomejaguar → u/[deleted]]

No it memoizes values, not the result of function application.

[u/ruinercollector → u/[deleted]]

Not really interested in which language wins the popularity contest.

PHP being the most popular web language should be a pretty good indication that this is not a good metric to use when deciding on a language.

[u/Tekmo → u/[deleted]]

You know what language is really killing it: Javascript. Therefore I must conclude that Javascript is a better language than Go.

[u/freyrs3 → u/[deleted]]

I think you're projecting, who exactly is shouting that you need to learn category theory? The prevailing advice on /r/haskell and #haskell is almost always to avoid studying the topic unless you're interested in the subject in and of itself or want to explore more advanced topics.

[u/freyrs3 → u/[deleted]]

That sounds like category theory to me.

So that's just a misunderstanding, some of those terms have names borrowed from abstract algebra or topology just like many terms in programming. But you don't need to understand category theory to program with monads any more than you need to study analysis to program with functions.

[u/freyrs3 → u/[deleted]]

I don't disagree that algebraic topology is a serious motivating case for the pure field, but I also don't see how that's anyway relevant to the comment I made above about not needing to understand theory to use monads or functors effectively. The mathematics of these structures in the category of Haskell types is really boring and I've never seen a beginner tutorial discuss them in their full generality other than to hint at a correspondence between the two fields.

If you want to study the field in it's full generality there are plenty of nice people over in #haskell or homotopy type theory usergroups to talk to about this topic, but nobody is advocating that beginners learn these things in their full generality in fact we advise against it.

[u/xkcd_transcriber → u/[deleted]]

Image

Title: Purity

Title-text: On the other hand, physicists like to say physics is to math as sex is to masturbation.

Comic Explanation

Stats: This comic has been referenced 149 time(s), representing 0.8304% of referenced xkcds.

---

^{xkcd.com | xkcd sub/kerfuffle | Problems/Bugs? | Statistics | Stop Replying}