“Functions are a first-class type” in swift?

Question

the little knowledge , I have about first class function is that it supports passing functions as arguments and we can also return them as the values in another function ... I a

Answer 1

A function that returns a function while capturing a value from the lexical environment:

A function of an array of Comparables that returns a function of a test predicate that returns a function of a value that returns a Bool if the value is the extreme of the array under test. (Currying)