Deriving not-so-complex types

(Wonderful image was modified from: https://openclipart.org/detail/123259/professeur-teacher)Often times, I get to read Haskell code with these patterns: (fmap . fmap), fmap (<*>), etc. I’ve just taken three of these types, and break these into their intuitions here in the hopes that somebody out there can understand when to use these. First we go with plain derivations of the final outcome, then

[lotz84]

fmap (<*>) とか fmap . fmap みたいな慣れないと分からないパターンを解説してくれてる #Haskell