[Haskell-cafe] ANN: To Kata Haskellen Evangelion

Olaf Klinke olf at aatal-apotheke.de
Tue Jul 30 19:31:03 UTC 2019

Isn't the Eq vs Ord problem similar to all sub-classes, e.g. 
Applicative vs. Monad, Semigroup vs. Monoid, Foldable vs. Traversable? 
What is the recommended way of coding? The Traversable module for example 
has default implementations of fmap and foldMap, as Functor and Foldable 
are superclasses. This suggests it is okay to define the subclass method 
first and derive the superclass methods from them. But arguments have been 
put up against this practice in particular cases, e.g. for AMP [1].


[1] https://mail.haskell.org/pipermail/haskell-cafe/2019-July/131259.html

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