module FunIn7 where --Any unused parameter to a definition can be removed. --To select a formal parameter, just need to stop the cursor at any position between the start --end position of this formal paramter. --In this example, remove '[x,y]' with a invalid cursor position foo [x,y]= h + t where (h,t) = head $ zip [1..10] [3..10] main :: Int main = foo [4,5]