Function composition test question.

compose.js

/**
 * Given any number of functions, returns a single function which acts as
 * if each function were called in right to left order. The result of each
 * function will be the argument to the next.
 *
 * To put it another way, compose(f, g)(x) should have the same result
 * as f(g(x)).
 *
 * @param {...Function} functions - Any number of input functions.
 */
function compose() {
  // TODO: implementation. Hint: do not add parameter names.
}

// TESTS:
var double = function(n) {
  return n * 2;
};

var increment = function(n) {
  return n + 1;
};

var f; // our test function

f = compose(double);
console.log("Expected: %d; actual: %d", 10, f(5));

f = compose(double, double, double);
console.log("Expected: %d; actual: %d", 16, f(2));

f = compose(double, increment, increment, increment, increment);
console.log("Expected: %d; actual: %d", 2, f(-3));