Bifunctor instance for (,) is not strictly law-abiding

David Feuer david.feuer at gmail.com
Wed Feb 17 19:25:13 UTC 2016


I don't think we should fix this, because it would break code, but I do
think we should document it.

Bifunctor law:

bimap id id = id

But actually,

bimap id id _|_ = (_|_, _|_)
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