feedback of William

[stevemao]

• The cheatsheet already has 'lateral' composition of functions using Applicative, but another thing that could be useful to add is lateral composition using mappend/(<>), since functions also implement Semigroup/Monoid.
• I'm somewhat surprised that there aren't any examples using the Klesli arrow with functions as the monad itself.

[sinogermany]

#2 has addressed the first bullet point, thanks to @stevemao 's awesome contribution.