[Haskell-cafe] A quick question about distribution of finite maps.

[Ignat Insarov]

Thanks Tom!

This is not a complete disaster theoretically, because a `mempty` map
corresponds to a function with `Void` domain which may not be invoked
anyway. But truly it makes the definition problematic, in the way
similar to how `Set` is not quite a functor — usually it works but
sometimes _map g ∘ map f_ may lose more elements than _map (g ∘ f)_.

I am not sure how much of sad I should be about it. The function still
works most of the time.