freeCodeCamp/challenges/object-oriented-and-functional-programming.json

{
  "name": "Object Oriented and Functional Programming",
  "order": 0.010,
  "note": [
    "Methods",
    "Closures",
    "Factories",
    "Pure Functions",
    "Currying Functions",
    "Functors",
    "Currying Functions"
  ],
  "challenges": [
    {
      "id":"cf1111c1c15feddfaeb1bdef",
      "title": "Declare JavaScript Objects as Variables",
      "difficulty":0,
      "description":[
        "Before we dive into Object Oriented Programming, let's revisit JavaScript objects.",
        "Give your <code>motorBike</code> object a <code>wheels</code>, <code>engine</code> and <code>seats</code> attribute and set them to numbers."
      ],
      "tests":[
        "assert(typeof(motorBike.engines) === 'number', '<code>engines</code> should be have a <code>engines</code> attribute set to a number.');",
        "assert(typeof(motorBike.wheels) === 'number', '<code>wheels</code> should be have a <code>engines</code> attribute set to a number.');",
        "assert(typeof(motorBike.seats) === 'number', '<code>seats</code> should be have a <code>engines</code> attribute set to a number.');"
      ],
      "challengeSeed":[
        "//Here is a sample Object",
        "var car = {",
        "  \"wheels\":4,",
        "  \"engines\":1,",
        "  \"seats\":5",
        "};",
        "",
        "//Now Let's make a similar Object called motorBike",
        "//Give it two wheels, one engine and one seat",
        "var motorBike = {",
        "  // Only change code below this line.",
        "",
        "",
        "",
        "  // Only change code above this line.",
        "};",
        "",
        "(function() {return(JSON.stringify(motorBike));})();"
      ],
      "challengeType":1,
          "type": "waypoint",
      "type": "waypoint"
    },
    {
      "id":"cf1111c1c15feddfaeb2bdef",
      "title": "Construct JavaScript Objects with Functions",
      "difficulty":0,
      "description":[
        "We are also able to create objects using <code>constructor</code> functions.",
        "Give your <code>motorBike</code> object a <code>wheels</code>, <code>engine</code> and <code>seats</code> attribute and set them to numbers."
      ],
      "tests":[
        "assert(typeof((new MotorBike()).engines) === 'number', '<code>engines</code> should be have a <code>engines</code> attribute set to a number.');",
        "assert(typeof((new MotorBike()).wheels) === 'number', '<code>wheels</code> should be have a <code>engines</code> attribute set to a number.');",
        "assert(typeof((new MotorBike()).seats) === 'number', '<code>seats</code> should be have a <code>engines</code> attribute set to a number.');"
      ],
      "challengeSeed":[
        "// Let's add the properties engine and seats to the car in the same way that the property wheels has been added below. They should both be numbers.",
        "var Car = function() {",
        "  this.wheels = 4;",
        "  this.engines = 1;",
        "  this.seats = 1;",
        "};",
        "",
        "var myCar = new Car();",
        "",
        "// Only change code below this line.",
        "var MotorBike = function() {",
        "",
        "",
        "",
        "};",
        "",
        "var myMotorBike = new MotorBike();",
        "// Only change code above this line.",
        "",
        "(function() {return(JSON.stringify(myMotorBike));})();"
      ],
      "challengeType":1,
      "type": "waypoint"
    },
    {
      "id":"cf1111c1c15feddfaeb3bdef",
      "title":"Make Object Properties Private",
      "difficulty":0,
      "description":[
        "Objects have their own attributes, called <code>properties</code>, and their own functions, called <code>methods</code>.",
        "In the previous challenge, we used the <code>this</code> keyword to reference <code>public properties</code> and <code>public methods</code> of the current object.",
        "We can also create <code>private properties</code> and <code>private methods</code>, which aren't accessible from outside the object.",
        "To do this, we omit the word <code>this</code> from the <code>property</code> or <code>method</code> declaration.",
        "See if you can keep <code>myBike.speed</code> and <code>myBike.addUnit</code> private, while making <code>myBike.getSpeed</code> publicly accessible."
      ],
      "tests":[
        "assert(typeof(myBike.getSpeed)!=='undefined' && typeof(myBike.getSpeed) === 'function', 'The method getSpeed of myBike should be accessible outside the object');",
        "assert(typeof(myBike.speed) === 'undefined', '<code>myBike.speed</code> should remain undefined.');",
        "assert(typeof(myBike.addUnit) === 'undefined', '<code>myBike.addUnit</code> should remain undefined.');"
      ],
      "challengeSeed":[
        "//Let's create an object with a two functions. One attached as a property and one not.",
        "var Car = function() {",
        "  this.gear = 1;",
        "  function addStyle(styleMe){",
        "    return('The Current Gear Is: ' + styleMe);",
        "  }",
        "  this.getGear = function() {",
        "    return(addStyle(this.gear));",
        "  };",
        "};",
        "",
        "var Bike = function() {",
        "  // Only change code below this line.",
        "  this.speed = 100;",
        "  function addUnit(value) {",
        "    return(value + \"KM/H\");",
        "  }",
        "  ",
        "  getSpeed = function () {",
        "    return(addUnit(speed));",
        "  };",
        "  ",
        "};",
        "",
        "// Only change code above this line.",
        "var myCar = new Car();",
        "var myBike = new Bike();",
        "",
        "if(myBike.hasOwnProperty('getSpeed')){(function() {return(JSON.stringify(myBike.getSpeed()));})();};"
      ],
      "challengeType":1,
      "type": "waypoint"
    },
    {
      "id":"cf1111c1c15feddfaeb4bdef",
      "title":"Make Instances of Objects with a Constructor Function",
      "difficulty":0,
      "description":[
        "Sometimes you'll want to be able to easily create similar objects.",
        "Objects have their own attributes, called <code>properties</code>, and their own functions, called <code>methods</code>.",
        "A function that creates objects is called a <code>constructor</code>.",
        "You can create <code>instances</code> of an object using a <code>constructor</code>.",
        "Each new <code>instance</code> of this object <code>inherits</code> all the <code>properties</code> and <code>methods</code> of your original object.",
        "Then you can give the instance new properties."
      ],
      "tests":[
        "assert((new Car()).wheels === 4, 'The property <code>wheels</code> should still be 4 like in the object constructor');",
        "assert(typeof((new Car()).engines) === 'undefined', 'There should not be a property engine in the object constructor');",
        "assert(myCar.wheels === 4, 'The property wheels of myCar should be four');",
        "assert(typeof(myCar.engines) === 'number', 'The property engine of myCar should be a number');"
      ],
      "challengeSeed":[
        "var Car = function() {",
        "   this.wheels = 4;",
        "};",
        "",
        "// Only change code below this line.",
        "var myCar = new Car();",
        "",
        "//Add the property \"engines\" to myCar, and make it a number.",
        "",
        "",
        "// Only change code above this line.",
        "(function() {return(JSON.stringify(myCar));})();"
      ],
      "challengeType":1,
      "type": "waypoint"
    },
    {
      "id":"cf1111c1c15feddfaeb7bdef",
      "title":"Iterate over Arrays with .map",
      "difficulty":0,
      "description":[
        "<code>array = array.map(function(val){</code>",
        "<code>&thinsp;&thinsp;return(val+1);</code>",
        "<code>});</code>",
        "",
        "The map method is one of the easiest ways to iterate through an array or object there is. Let's use it now."
      ],
      "tests":[
        "assert.deepEqual(array, [4,5,6,7,8], 'You should have added three to each value in the array');",
        "assert(editor.getValue().match(/\\.map\\(/gi), 'You should be making use of the map method');",
        "assert(editor.getValue().match(/\\[1\\,2\\,3\\,4\\,5\\]/gi), 'You should only modify the array with .map');"
      ],
      "challengeSeed":[
        "//Use map to add three to each value in the array",
        "var array = [1,2,3,4,5];",
        "// Only change code below this line.",
        "",
        "",
        "",
        "// Only change code above this line.",
        "(function() {return(array);})();"
      ],
      "challengeType":1,
      "type": "waypoint"
    },
    {
      "id":"cf1111c1c15feddfaeb8bdef",
      "title":"Condense arrays with .reduce",
      "difficulty":0,
      "description":[
        "Reduce can be useful for condensing and array or numbers into one value.",
        "<code>var singleVal = array.reduce(function(previousVal, currentVal){</code>",
        "<code>&thinsp;&thinsp;return(previousVal+currentVal);</code>",
        "<code>});</code>"
      ],
      "tests":[
        "assert(singleVal == 30, 'singleVal should have been set to the result of you reduce operation');",
        "assert(editor.getValue().match(/\\.reduce\\(/gi), 'You should have made use of the reduce method');"
      ],
      "challengeSeed":[
        "var array = [4,5,6,7,8];",
        "var singleVal = 0;",
        "// Only change code below this line.",
        "",
        "",
        "",
        "// Only change code above this line.",
        "(function() {return(singleVal);})();"
      ],
      "challengeType":1,
      "type": "waypoint"
    },
    {
      "id":"cf1111c1c15feddfaeb9bdef",
      "title":"Filter Arrays with .filter",
      "difficulty":0,
      "description":[
        "filter is a useful method that can filter out values that don't match a certain criteria",
        "Let's remove all the values greater than five",
        "<code>array = array.filter(function(val) {</code>",
        "<code>&thinsp;&thinsp;return(val<4);</code>",
        "<code>});</code>"
      ],
      "tests":[
        "assert.deepEqual(array, [1,2,3,4,5], 'You should have removed all the values from the array that are greater than five');",
        "assert(editor.getValue().match(/array\\.filter\\(/gi), 'You should be using the filter method to remove the values from the array');",
        "assert(editor.getValue().match(/\\[1\\,2\\,3\\,4\\,5\\,6\\,7\\,8\\,9\\,10\\]/gi), 'You should only be using .filter to modify the contents of the array');"
      ],
      "challengeSeed":[
        "var array = [1,2,3,4,5,6,7,8,9,10];",
        "  // Only change code below this line.",
        "",
        "",
        "",
        "  // Only change code above this line.",
        "(function() {return(array);})();"
      ],
      "challengeType":1,
      "type": "waypoint"
    },
    {
      "id":"cf1111c1c16feddfaeb1bdef",
      "title": "Sort Arrays with .sort",
      "difficulty":0,
      "description":[
        "You can use the method sort to easily sort the values in the array alphabetically or numerically",
        "<code>var array = [1,3,2];</code>",
        "<code>array = array.sort();</code>",
        "This will return <code>[1, 2, 3]</code>"
      ],
      "tests":[
        "assert.deepEqual(array, ['alpha', 'beta', 'charlie'], 'You should have sorted the array alphabetically');",
        "assert(editor.getValue().match(/\\[\\'beta\\'\\,\\s\\'alpha\\'\\,\\s'charlie\\'\\];/gi), 'You should be sorting the array using sort');",
        "assert(editor.getValue().match(/\\.sort\\(\\)/gi), 'You should have made use of the sort method');"
      ],
      "challengeSeed":[
        "var array = ['beta', 'alpha', 'charlie'];",
        "// Only change code below this line.",
        "",
        "",
        "",
        "  // Only change code above this line.",
        "(function() {return(array);})();"
      ],
      "challengeType":1,
      "type": "waypoint"
    },
    {
      "id": "cf1111c1c16feddfaeb2bdef",
      "title": "Reverse Arrays with .reverse",
      "difficulty": 0,
      "description": [
        "You can use the <code>.reverse()</code> function to reverse the contents of an array."
      ],
      "tests": [
        "assert.deepEqual(array, [7,6,5,4,3,2,1], 'You should reverse the array');",
        "assert(editor.getValue().match(/\\.reverse\\(\\)/gi), '');",
        "assert(editor.getValue().match(/\\[1\\,2\\,3\\,4\\,5\\,6\\,7/gi), '');"
      ],
      "challengeSeed": [
        "var array = [1,2,3,4,5,6,7];",
        "  // Only change code below this line.",
        "",
        "",
        "",
        "  // Only change code above this line.",
        "(function() {return(array);})();"
      ],
      "challengeType": 1,
      "type": "waypoint"
    },
    {
      "id": "cf1111c1c16feddfaeb3bdef",
      "title": "Concatenate Strings with .concat",
      "difficulty": 0,
      "description": [
        "<code>.concat()</code> can be used to merge the contents of two arrays into one.",
        "<code>array = array.concat(otherArray);</code>"
      ],
      "tests": [
        "assert.deepEqual(array, [1,2,3,4,5,6], 'You should concat the two arrays together');",
        "assert(editor.getValue().match(/\\.concat\\(/gi), 'You should be using the concat method to merge the two arrays');",
        "assert(editor.getValue().match(/\\[1\\,2\\,3\\]/gi) && editor.getValue().match(/\\[4\\,5\\,6\\]/gi), 'You should only modify the two arrays without changing the origional ones');"
      ],
      "challengeSeed": [
        "var array = [1,2,3];",
        "",
        "var concatMe = [4,5,6];",
        "// Only change code below this line.",
        "",
        "",
        "",
        "// Only change code above this line.",
        "(function() {return(array);})();"
      ],
      "challengeType": 1,
      "type": "waypoint"
    },
    {
      "id":"cf1111c1c16feddfaeb4bdef",
      "title":"Split Strings with .split",
      "difficulty":0,
      "description":[
        "You can use the <code>.split()</code> method to split a string into an array.",
        "split uses the argument you give to to split the string.",
        "<code>array = string.split(' ');</code>"
      ],
      "tests":[
        "assert(typeof(array) === 'object' && array.length === 5, 'You should have split the string by it\\'s spaces');",
        "assert(/\\.split\\(/gi, 'You should have made use of the split method on the string');"
      ],
      "challengeSeed":[
        "var string = \"Split me into an array\";",
        "// Only change code below this line.",
        "",
        "var array = string;",
        "",
        "// Only change code above this line.",
        "(function() {return(array);})();"
      ],
      "challengeType":1,
      "type": "waypoint"
    },
    {
      "id":"cf1111c1c16feddfaeb5bdef",
      "title":"Join Strings with .join",
      "difficulty":0,
      "description":[
        "We can use the <code>.join()</code> method to join each element in an array into a string separated by whatever delimiter you provide as an argument to the join operation.",
        "<code>var joinMe = joinMe.join(\" \");</code>"
      ],
      "tests":[
        "assert(typeof(joinMe) === 'string' && joinMe === \"Split me into an array\", 'You should have joined the arrays by it\\'s spaces');",
        "assert(/\\.join\\(/gi, 'You should have made use of the join method on the array');"
      ],
      "challengeSeed":[
        "var joinMe = [\"Split\",\"me\",\"into\",\"an\",\"array\"];",
        "// Only change code below this line.",
        "",
        "joinMe = joinMe;",
        "",
        "// Only change code above this line.",
        "(function() {return(joinMe);})();"
      ],
      "challengeType":1,
      "type": "waypoint"
    }
  ]
}