### pipe Performs left-to-right function composition. Use `Array.reduce()` with the spread operator (`...`) to perform left-to-right function composition. The first (leftmost) function can accept one or more arguments; the remaining functions must be unary. ```js const pipeFunctions = (...fns) => fns.reduce((f, g) => (...args) => g(f(...args))); ``` ```js const add5 = x => x + 5 const multiply = (x, y) => x * y const multiplyAndAdd5 = pipeFunctions(multiply, add5) multiplyAndAdd5(5, 2) // 15 ```