{ "name": "Object Oriented and Functional Programming", "order": 7, "time": "1h", "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 motorBike object a wheels, engines and seats attribute and set them to numbers." ], "tests":[ "assert(typeof(motorBike.engines) === 'number', 'message: motorBike should have a engines attribute set to a number.');", "assert(typeof(motorBike.wheels) === 'number', 'message: motorBike should have a wheels attribute set to a number.');", "assert(typeof(motorBike.seats) === 'number', 'message: motorBike should have a seats 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 constructor functions.", "Give your myMotorBike object a wheels, engines and seats attribute and set them to numbers." ], "tests":[ "assert(typeof((new MotorBike()).engines) === 'number', 'message: myMotorBike should have a engines attribute set to a number.');", "assert(typeof((new MotorBike()).wheels) === 'number', 'message: myMotorBike should have a wheels attribute set to a number.');", "assert(typeof((new MotorBike()).seats) === 'number', 'message: myMotorBike should have a seats attribute set to a number.');" ], "challengeSeed":[ "// Let's add the properties engines 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 properties, and their own functions, called methods.", "In the previous challenge, we used the this keyword to reference public properties and public methods of the current object.", "We can also create private properties and private methods, which aren't accessible from outside the object.", "To do this, we omit the word this from the property or method declaration.", "See if you can keep myBike.speed and myBike.addUnit private, while making myBike.getSpeed publicly accessible." ], "tests":[ "assert(typeof(myBike.getSpeed)!=='undefined' && typeof(myBike.getSpeed) === 'function', 'message: The method getSpeed of myBike should be accessible outside the object.');", "assert(typeof(myBike.speed) === 'undefined', 'message: myBike.speed should be undefined.');", "assert(typeof(myBike.addUnit) === 'undefined', 'message: myBike.addUnit should remain undefined.');" ], "challengeSeed":[ "//Let's create an object with 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 properties, and their own functions, called methods.", "A function that creates objects is called a constructor.", "You can create instances of an object using a constructor.", "Each new instance of this object inherits all the properties and methods of your original object.", "Once an instance has been created you can add properties to that instance individually.", "Add an engines property with a number value to the myCar instance." ], "tests":[ "assert((new Car()).wheels === 4, 'message: The property wheels should still be 4 in the object constructor.');", "assert(typeof((new Car()).engines) === 'undefined', 'message: There should not be a property engines in the object constructor.');", "assert(myCar.wheels === 4, 'message: The property wheels of myCar should equal 4.');", "assert(typeof(myCar.engines) === 'number', 'message: The property engines 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":[ "The map method is one of the easiest ways to iterate through an array or object there is. Let's use it now.", "array = array.map(function(val){", "  return val+1;", "});", "", "Use the map function to add 3 to every value in the variable array." ], "tests":[ "assert.deepEqual(array, [4,5,6,7,8], 'message: You should add three to each value in the array.');", "assert(editor.getValue().match(/\\.map\\s*\\(/gi), 'message: You should be making use of the map method.');", "assert(editor.getValue().match(/\\[1\\,2\\,3\\,4\\,5\\]/gi), 'message: 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;})();" ], "MDNlinks":[ "Array.map()" ], "challengeType":1, "type": "waypoint" }, { "id":"cf1111c1c15feddfaeb8bdef", "title":"Condense arrays with .reduce", "difficulty":0, "description":[ "Reduce can be useful for condensing an array of numbers into one value.", "var singleVal = array.reduce(function(previousVal, currentVal){", "  return previousVal+currentVal;", "});", "Use the reduce function to sum all the values in array and assign it to singleVal." ], "tests":[ "assert(singleVal == 30, 'message: singleVal should be equal to the sum of all items in the array variable.');", "assert(editor.getValue().match(/\\.reduce\\s*\\(/gi), 'message: 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;})();" ], "MDNlinks":[ "Array.reduce()" ], "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", "array = array.filter(function(val) {", "  return val <= 5;", "});" ], "tests":[ "assert.deepEqual(array, [1,2,3,4,5], 'message: You should have removed all the values from the array that are greater than 5.');", "assert(editor.getValue().match(/array\\.filter\\s*\\(/gi), 'message: 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), 'message: 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;})();" ], "MDNlinks":[ "Array.filter()" ], "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.", "var array = [1, 3, 2];", "array = array.sort();", "array is now [1, 2, 3].", "Use sort to sort array alphabetically." ], "tests":[ "assert.deepEqual(array, ['alpha', 'beta', 'charlie'], 'message: You should have sorted the array alphabetically.');", "assert(editor.getValue().match(/\\[\\'beta\\'\\,\\s\\'alpha\\'\\,\\s'charlie\\'\\];/gi), 'message: You should only be using .sort to modify the array.');", "assert(editor.getValue().match(/\\.sort\\s*\\(\\)/gi), 'message: 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;})();" ], "MDNlinks":[ "Array.sort()" ], "challengeType":1, "type": "waypoint" }, { "id": "cf1111c1c16feddfaeb2bdef", "title": "Reverse Arrays with .reverse", "description": [ "You can use the reverse function to reverse the contents of an array.", "Add a line of code that uses reverse to reverse the array variable." ], "tests": [ "assert.deepEqual(array, [7,6,5,4,3,2,1], 'message: You should reverse the array.');", "assert(editor.getValue().match(/\\.reverse\\s*\\(\\)/gi), 'message: You should use the reverse method.');", "assert(editor.getValue().match(/\\[1\\,2\\,3\\,4\\,5\\,6\\,7/gi), 'message: You should only be using revserse to modify array.');" ], "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;})();" ], "MDNlinks":[ "Array.reverse()" ], "challengeType": 1, "type": "waypoint" }, { "id": "cf1111c1c16feddfaeb3bdef", "title": "Concatenate Strings with .concat", "description": [ ".concat() can be used to merge the contents of two arrays into one.", "array = array.concat(otherArray);", "Use .concat() to concatenate concatMe onto the end of array and assign it back to array." ], "tests": [ "assert.deepEqual(array, [1,2,3,4,5,6], 'message: You should concat the two arrays together.');", "assert(editor.getValue().match(/\\.concat\\s*\\(/gi), 'message: 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), 'message: You should only be using concat to modify the arrays.');" ], "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;})();" ], "MDNlinks":[ "Array.concat()" ], "challengeType": 1, "type": "waypoint" }, { "id":"cf1111c1c16feddfaeb4bdef", "title":"Split Strings with .split", "difficulty":0, "description":[ "You can use the .split() method to split a string into an array.", ".split() uses the argument you pass in as a delimiter to determine which points the string should be split at.", "var array = string.split(' ');", "Use .split() to create an array of words from string and assign it to array." ], "tests":[ "assert(typeof(array) === 'object' && array.length === 5, 'message: You should split the string by its spaces.');", "assert(/\\.split\\(/gi, 'message: You should use 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;})();" ], "MDNlinks":[ "String.split()" ], "challengeType":1, "type": "waypoint" }, { "id":"cf1111c1c16feddfaeb5bdef", "title":"Join Strings with .join", "difficulty":0, "description":[ "We can use the .join() method to join each element in an array into a string separated by whatever delimiter you provide as an argument to the join operation.", "var joinMe = joinMe.join(\" \");", "Use the .join() method to create a string from joinMe with spaces in between each element and assign it back to joinMe." ], "tests":[ "assert(typeof(joinMe) === 'string' && joinMe === \"Split me into an array\", 'message: You should join the elements of the array with spaces.');", "assert(/\\.join\\(/gi, 'message: You should 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;})();" ], "MDNlinks":[ "Array.join()" ], "challengeType":1, "type": "waypoint" } ] }