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Comment by wereHamster | Hacker News Reader

Serious question. In the following code, what would be better function / type names? (or you can pick another bit of Haskell code that you know and/or have particular trouble understanding).

    class Foldable t where
        foldl :: (b -> a -> b) -> b -> t a -> b

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Maybe something like:

  class Foldable myFoldable where
    foldl :: (summary -> element -> summary) 
          -> summary 
          -> myFoldable element 
          -> summary

This is the translation I do in my head when I read that type signature, at least.

Really? I find the single-letter version far easier to read.

The single letter version is far easier since I already know what foldable does. Not so much when I'm learning a new library.

I wonder if anyone has worked on a Prelude replacement which has these replacements (along with renaming functions where appropriate)...

To change the names you'd have to re-implement all the functions. Good luck with that, base is /large/.

This is a documentation issue, not an implementation issue.

Wow. That's much better.

Apparently-idiomatic Haskell reads (or, rather, doesn't) about like line-noise/code-golf style Perl to me.

The problem with this is that there are Foldables that do not behave in the way that is implied by the above re-write of the parameters.

I think this is kind of the problem when you are really high up in abstraction-land. The functions that you're using are so generic that it's hard to say that they operate on anything in particular, except that the arguments fulfill certain properties or laws.

I've always disliked mapM_. Something about it just looks ugly and it doesn't really hint what its for. I would like to see mapM as mapMonad and mapM_ as eachMonad. Of course, once I knew what it meant the abbreviations became rather nice.

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