In the process of learning haskell, I’ve been trying to become comfortable with the function applicator (‘$’) and function composition (‘.’). Here is some code to show how they relate (and how they relate to using parenthesis to enforce order of operations):
let dict = [(1,'a'),(2,'b'),(3,'c')] -- The following 3 lines of code are equivalent... snd . head . filter (\item@(k,v) -> k == 2) $ dict -- returns 'b' snd $ head $ filter (\item@(k,v) -> k == 2) dict -- returns 'b' snd (head (filter (\item@(k,v) -> k == 2) dict)) -- return 'b'
