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Comment by jfecher | Hacker News Reader

map2 is indeed another name for zipWith. I believe I got that name from Racket if memory serves. Compared to zipWith I like its symmetry with the 1 argument map. I also wasn't aware of bimap! I can't seem to find a function of that name online, though I did find the BiMap haskell package, is that what you're referring to?

And yes, the dot product should be 32, thank you :)

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Not OP but they meant https://hackage.haskell.org/package/base-4.16.1.0/docs/Data-...

As you have the normal map function for Functors (using Haskell):

  > :t fmap
  fmap :: Functor f => (a -> b) -> f a -> f b

you can have bimap for Bifunctors:

  > :t bimap
  bimap :: Bifunctor p => (a -> b) -> (c -> d) -> p a c -> p b d

which specialised to pairs is:

  > :t bimap @(,)
  bimap @(,) :: (a -> b) -> (c -> d) -> (a, c) -> (b, d)

I was wondering why the dot product wasn't 32! Good thing I checked. Also this seems like a cool new language, I need to learn a functional language, I wonder how far this language will go in development.

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