Swift Functional Programming - Second Edition

A composed function with custom operator

Let's define a new custom operator to use instead of our composed function:

precedencegroup AssociativityLeft {     associativity: left } infix operator |> : AssociativityLeft func |> <T, V>(f: @escaping (T) -> V, g: @escaping (V) -> V ) -> (T) -> V {     return { x in g(f(x)) } } let composedWithCustomOperator = extractElements |> formatWithCurrency composedWithCustomOperator("10,20,40,30,80,60") // The result will be: ["10$", "20$", "40$", "30$", "80$", "60$"] 

In this example, we have defined a new operator, |>, that takes two generic functions and combines them, returning a function that has the first function's input as the parameter and the second function's return as the return type.

As this new ...