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

Ignat Insarov kindaro at gmail.com
Sat Jan 9 11:30:08 UTC 2021

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.

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