text: var _ // globals
  
  /* This section uses a functional extension known as Underscore.js - http://documentcloud.github.com/underscore/
       "Underscore is a utility-belt library for JavaScript that provides a lot of the functional programming support
        that you would expect in Prototype.js (or Ruby), but without extending any of the built-in JavaScript objects.
        It's the tie to go along with jQuery's tux."
   */
  describe('About Higher Order Functions', function () {
    it('should use filter to return array items that meet a criteria', function () {
      var numbers = [1, 2, 3]
      var odd = _(numbers).filter(function (x) { return x % 2 !== 0 })
  
      expect(odd).toEqual([1, 3])
      expect(odd.length).toBe(2)
      expect(numbers.length).toBe(3)
    })
  
    it("should use 'map' to transform each element", function () {
      var numbers = [1, 2, 3]
      var numbersPlus1 = _(numbers).map(function (x) { return x + 1 })
  
      expect(numbersPlus1).toEqual([2, 3, 4])
      expect(numbers).toEqual([1, 2, 3])
    })
  
    it("should use 'reduce' to update the same result on each iteration", function () {
      var numbers = [1, 2, 3]
      var reduction = _(numbers).reduce(
              function (/* result from last call */ memo, /* current */ x) { return memo + x }, /* initial */ 0)
  
      expect(reduction).toBe(6)
      expect(numbers).toEqual([1, 2, 3])
    })
  
    it("should use 'forEach' for simple iteration", function () {
      var numbers = [1, 2, 3]
      var msg = ''
      var isEven = function (item) {
        msg += (item % 2) === 0
      }
  
      _(numbers).forEach(isEven)
  
      expect(msg).toEqual('')
      expect(numbers).toEqual()
    })
  
    it("should use 'all' to test whether all items pass condition", function () {
      var onlyEven = [2, 4, 6]
      var mixedBag = [2, 4, 5, 6]
  
      var isEven = function (x) { return x % 2 === 0 }
  
      expect(_(onlyEven).all(isEven)).toBe(true)
      expect(_(mixedBag).all(isEven)).toBe(false)
    })
  
    it("should use 'any' to test if any items passes condition", function () {
      var onlyEven = [2, 4, 6]
      var mixedBag = [2, 4, 5, 6]
  
      var isEven = function (x) { return x % 2 === 0 }
  
      expect(_(onlyEven).any(isEven)).toBe(FILL_ME_IN)
      expect(_(mixedBag).any(isEven)).toBe(FILL_ME_IN)
    })
  
    it('should use range to generate an array', function () {
      expect(_.range(3)).toEqual(FILL_ME_IN)
      expect(_.range(1, 4)).toEqual(FILL_ME_IN)
      expect(_.range(0, -4, -1)).toEqual(FILL_ME_IN)
    })
  
    it('should use flatten to make nested arrays easy to work with', function () {
      expect(_([ [1, 2], [3, 4] ]).flatten()).toEqual(FILL_ME_IN)
    })
  
    it('should use chain() ... .value() to use multiple higher order functions', function () {
      var result = _([ [0, 1], 2 ]).chain()
                         .flatten()
                         .map(function (x) { return x + 1 })
                         .reduce(function (sum, x) { return sum + x })
                         .value()
  
      expect(result).toEqual(FILL_ME_IN)
    })
  })
  
  