Re: [Haskell-cafe] Need ideas how to model the lack of something

Am 15.12.2015 um 01:40 schrieb Thomas Koster:

On Mon, Dec 14, 2015 at 3:15 AM, martin wrote:

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I started like this

data C a = C { insert :: a -> Maybe (C a), remove :: Maybe (a, C a) }

but I could not implement anything sensible on top of this.

Am 14.12.2015 um 01:28 schrieb Kim-Ee Yeoh:

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And the reason you're stuck implementing anything sensible on top of this is because you've written an OOP-style specification of a data structure.

On 14 December 2015 at 17:28, Joachim Durchholz wrote:

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Mmm... this is the second time this has been raised. What's the problem with OOP style? Something specific with Haskell, something about OOP in general, something else?

Nothing nefarious: Object-oriented style in Haskell is wordy and unnatural for no other reason than that Haskell is a functional programming language and not an object-oriented language.

I see Kim-Ee Yeoh stating that Martin is stuck without a way forward due to using OO style, which seems more serious than just "wordy and unnatural". Or am I misreading his words, and that "OO-style" reference was just descriptive rather than presenting the base cause of Martin's problems? Regards, Jo P.S.: I'm not trying to criticize anything, just trying to understand what the issue is. Is there a webpage like "Haskell for OO-warped minds" that explains how to transition one's idioms? I have a good grasp of Haskell in-the-small, but I haven't had an opportunity to learn the larger-scale issues, so I'm probably just being dense and would like to change that.