User talk:2A00:23C5:C501:6900:2432:D16:23F5:A564

The expression (<$> Just 3 ) <$> (+) <$> Just 2 is very elegant, but I don't think anyone learning Haskell will be able to parse this easily. It needs a careful read of the Haskell report to understand it.

As a matter of style, surely redundant brackets should be inserted in any expression where the structure is not obvious? Certainly here, in an explanation of applicative functors, it is placing an extra and distracting cognitive load on the reader.

The book seems to skim very lightly over parsing in Haskell. It really needs some extra material in this area.