Re: [Haskell-cafe] Documenting strictness properties for Data.Map.Strict

Johan Tibell wrote:

map (\ v -> undefined)  ==  undefined mapKeys (\ k -> undefined)  ==  undefined

Not really related to the question but I don't really understand how these properties can possibly hold. Shouldn't it be: map (\v -> undefined) x = undefined And even then, does this really hold for empty maps? Roman