21 Feb
2016
21 Feb
'16
7:57 a.m.
Marcin Mrotek wrote
I think that, as far as Foldable is concerned, a tuple is equivalent to Identity, so this instance is indeed useless. However, Foldable is a superclass of Traversable (and it wouldn't make much sense to make these classes unrelated, as one can always define folds with `traverse`), so I've always found it a necessary evil.
Perhaps the case of tuple is evidence that Foldable should *not* be a superclass of Traversable? -- View this message in context: http://haskell.1045720.n5.nabble.com/Proposal-Add-conspicuously-missing-Func... Sent from the Haskell - Libraries mailing list archive at Nabble.com.