>>>>> "SP" == Sven Panne <svenpanne@gmail.com> writes: SP> Am Mo., 23. Nov. 2020 um 14:54 Uhr schrieb Johannes Waldmann SP> <johannes.waldmann@htwk-leipzig.de>: [...] Henning already SP> called this "Matlab league" behaviour, SP> https://mail.haskell.org/pipermail/libraries/2016-February/026678.html What is the intiutive way of implementing the tuple instance like this [1] instance Foldable ((,) a) where .. length _ = 1 .. I cannot come up with a real argument, except to say there is something. For instance for Either, Left returns 0, and Right 1. But that there is something isn't that already implied by the tuple? And even if that would be the argument, the ⊥-case is not considered as the argument is not evaluated. [1] https://hackage.haskell.org/package/base-4.14.0.0/docs/src/Data.Foldable.htm...