The APL/J/K/Klong versions are more general; they all work for a variety of ranks of input, whereas the Haskell version- which is the longest and most visually

The APL/J/K/Klong versions are more general; they all work for a variety of ranks of input, whereas the Haskell version- which is the longest and most visually noisy- bakes in a single rank's mapping explicitly.