ES6 function decorators

decorate.js

function decorate (...functions) {
  return functions.reduce(
    (a, b) => b(a),
    functions.pop() // Pop wrapped function as initial value
  );
};

decorate(
  (func) => (text) => func(text.toUpperCase() + "!"), // Outer-wrapper
  (func) => (text) => func(text.toLowerCase() + "…"), // Inner-wrapper
  (text) => console.log(text)                         // Wrapped
)(
  "Hello World"
);

// Output: "HELLO WORLD…!"