Observe: ```haskell ghci> :set -Woperator-whitespace ghci> f = \x y -> x* y ghci> f = \x y -> x. y ghci> f = \x y -> x- y ghci> f = \x y -> x+ y <interactive>:5:14: warning: [-Woperator-whitespace] The suffix use of a ‘+’ might be repurposed as special syntax by a future language extension. Suggested fix: add whitespace around it. ``` That’s because these operators are `ITstar`, `ITdot`, and `ITminus` respectively, rather than `ITvarsym`. So they are handled by a different codepath which does not generate the warning.