Haskell Foldable Wats

Kosyrev Serge _deepfire at feelingofgreen.ru
Wed Feb 24 15:19:44 UTC 2016

Nathan Bouscal <nbouscal at gmail.com> writes:
> What you seem to be saying, though, is one of two things.
> 1: "In all contexts, you should only ever use tuples for this purpose", or 
> 2: "If you find another purpose to use tuples for, you shouldn't use them as Functors"
> Option 2 is more humble in that it allows for the possibility that
> there's a use-case you're unfamiliar with, but instead it just makes
> an arbitrary decision that, whatever this unfamiliar use-case is,
> surely they shouldn't be using Functor. I don't see any way to justify
> that position.

This kind of argument is defeatable by replacing Functor with Monad
(which, I'm sure, we can find a some instance of), or some other, even
more specific type class -- the argument becomes absurd, without
having its structure changed.

Where do we stop?

с уважениeм / respectfully,
Косырев Сергей

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