I think you’ll get (k1+k2) *2 only if you can make sure non of the map values is whatever you store in the map as an intermediate representation for “there were matching keys with two separate values”.
LostKobrakai
codeanpeace
I like how the case statement makes this approach very readable.
Just wanted to add that, depending on how often both maps contain overlapping keys, it could make sense to manually remove duplicated keys e.g. Map.keys(a) ++ Map.keys(b) |> Enum.uniq.
Map.new/2 already removes duplicated keys with the latest one prevailing. But that means it would unnecessarily run through the case statement twice whenever a key exists in both maps.
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