Coming from a ClojureScript / Reagent background, functional components and hooks look very natural, useState being largely equivalent to reagent.core/atom. useEffect and useRef look like a logical extension of the same idea.
Clojure's * can accept any number of arguments, including zero (returns 1 in this case), one (acts as identity function on numbers) or more than two (returns the product of all arguments). This helps to simplify arithmetic expressions in some cases (e. g. polynominals) and allows to calculate a sum or product of any sequence, including empty one, using (reduce * xs)