From the article: > I want it to be the case that this function only actually calls do-something-very-expensive once per unique value of x, even across separat

From the article: > I want it to be the case that this function only actually calls do-something-very-expensive once per unique value of x, even across separate invocations of dumb-example. My code memoizes results of function FIB _inside_ the lambda assigned to EXAMPLE, even across separate invocations of EXAMPLE.