"A comment is a very useful line of code that is not actually ran by the machine executing it. With this property comments are the perfect way of creating notes to yourself or anyone else who reads your code describing what the code does",
"It's an extremely important part in writing good, efficient and maintainable code and a requirement by most employers",
"Let's take a look at the two ways in which we can write a comment in JavaScript",
"<code> //This is a comment </code>",
"These comment out the entire line that they are on",
"<code> /*This also is a comment*/ </code>",
"These comment out everything in between <code> /* </code> and <code> */ </code>",
"Try creating one of each now."
],
"tests":[
"assert(editor.getValue().match(/(\\/\\*)...../g), 'Make sure you have at least one \/\\* \\*\/ style comment that has at least five letters in it');",
"assert(editor.getValue().match(/(\\*\\/)/g), 'Make sure that you close the coment with a \\*\/');",
"assert(editor.getValue().match(/(\\/\\/)...../g), 'Make sure that there is at least one \\/\\/ style comment with at least five letters in it');"
"A boolean is a type of variable that represents either true or false (Named after the British mathematician George Boole).",
"Booleans are often the result of a function or a comparative operation, for example <code> 1==1 </code> is true whereas <code> 1==2 </code> is false.",
"They are most commonly found inside <code> if </code> statements which we shall cover later",
"For now Let's modify our <code> welcomeToBooleans </code> function so that it will return <code> true </code> instead of <code> false </code> when the run button is clicked"
"Be sure to use lowercase and uppercase letters properly. JavaScript variables are written in <code>camel case</code>. An example of camel case is: camelCase.",
"Look at the <code>ourName</code> example if you get stuck."
"assert((function(){/**/if(typeof(myName) !== 'undefined' && typeof(myName) == 'string' && myName.length > 0){return(true);}else{return(false);}/**/})(), 'myName should be a string that contains at least one character in it');"
"assert((function(){if(typeof(myFirstName) !== 'undefined' && typeof(myFirstName) == 'string' && myFirstName.length > 0){return(true);}else{return(false);}})(), 'myFirstName should be a string with a least one character in it');",
"assert((function(){if(typeof(myLastName) !== 'undefined' && typeof(myLastName) == 'string' && myLastName.length > 0){return(true);}else{return(false);}})(), 'myLastName should be a string with a least one character in it');"
"Use the <code>.length</code> property to count the number of characters in the <code>lastNameLength</code> variable.",
"For example, if we created a variable <code>var firstName = \"Julie\"</code>, we could find out how long the string \"Julie\" is by using the <code>firstName.length</code> property."
"Use <code>bracket notation</code> to find the first character in a the <code>firstLetterOfLastName</code> variable.",
"<code>Bracket notation</code> is a way to get a character at a specific <code>index</code> within a string.",
"Computers don't start counting at 1 like humans do. They start at 0.",
"For example, the character at index 0 in the word \"Julie\" is \"J\". So if <code>var firstName = \"Julie\"</code>, you can get the value of the first letter of the string by using <code>firstName[0]</code>.",
"Try looking at the <code>firstLetterOfFirstName</code> variable declaration if you get stuck."
"assert((function(){if(typeof(firstLetterOfLastName) != 'undefined' && typeof(firstLetterOfLastName) == 'string' && firstLetterOfLastName == 'C'){return(true);}else{return(false);}})(), 'The first letter of firstLetterOfLastName should be a C');"
"Just like the last lesson where we used <code> Bracket Notation </code> to access the first letter we can use the same method to get the letters ar other positions",
"Don't forget that computers start counting at 0 so the first letter is actually the zeroth one",
"Let's now try to set <code> thirdLetterOfLastName </code> to equal the <code>third letter</code> of the <code> lastName </code> variable",
"Use <code>bracket notation</code> to find the last character in the <code>lastName</code> variable.",
"For example, the character at index 0 in the word \"Julie\" is \"J\". So if <code>var firstName = \"Julie\"</code>, you can get the value of the first letter of the string by using <code>firstName[0]</code>.",
"In order to get the last letter of a string, you can subtract one from the string's length.",
"For example, if <code>var firstName = \"Julie\"</code>, you can get the value of the last letter of the string by using <code>firstName[firstName.length - 1]</code>.",
"Try looking at the <code>lastLetterOfLastName</code> variable declaration if you get stuck."
"Use <code>bracket notation</code> to find the second-to-last character in the <code>lastName</code> variable.",
"For example, the character at index 0 in the word \"Julie\" is \"J\". So if <code>var firstName = \"Julie\"</code>, you can get the value of the first letter of the string by using <code>firstName[0]</code>.",
"In order to get the last letter of a string, you can subtract one from the string's length.",
"For example, if <code>var firstName = \"Julie\"</code>, you can get the value of the third-to-last letter of the string by using <code>firstName[firstName.length - 3]</code>.",
"Try looking at the <code>lastLetterOfLastName</code> variable declaration if you get stuck."
"In JavaScript whole numbers (called integers) can be really easily to preform mathematical functions",
"Let's try a few of the most commonly used ones now",
"We use <code> + </code> for addition",
"Replace the <code> 0 </code> with correct number to achieve the result in the comment."
],
"tests":[
"assert((function(){if(add == 20 && editor.getValue().match(/\\+/g)){return(true);}else{return(false);}})(), 'Add should be the result of a sum and be equal to 20');"
"In JavaScript whole numbers (called integers) can be really easily to preform mathematical functions",
"Let's try a few of the most commonly used ones now",
"We use <code> - </code> for subtraction",
"Replace the <code> 0 </code> with correct number to achieve the result in the comment."
],
"tests":[
"assert((function(){if(subtract == 12 && editor.getValue().match(/\\-/g)){return(true);}else{return(false);}})(), 'Subtract should be the result of a sum and be equal to 12');"
"In JavaScript whole numbers (called integers) can be really easily to preform mathematical functions",
"Let's try a few of the most commonly used ones now",
"We use <code> * </code> for multiplication",
"Replace the <code> 0 </code> with correct number to achieve the result in the comment."
],
"tests":[
"assert((function(){if(multiply == 80 && editor.getValue().match(/\\*/g)){return(true);}else{return(false);}})(), 'Multiply should be the result of a sum and be equal to 80');"
"In JavaScript whole numbers (called integers) can be really easily to preform mathematical functions",
"Let's try a few of the most commonly used ones now",
"We use <code> / </code> for division",
"Replace the <code> 0 </code> with correct number to achieve the result in the comment."
],
"tests":[
"assert((function(){if(divide == 2 && editor.getValue().match(/\\//g)){return(true);}else{return(false);}})(), 'Divide should be the result of a sum and be equal to 2');"
],
"challengeSeed":[
"var divide = 66 / 0;//equals 2",
"",
"",
"",
"(function(z){return('divide='+z);})(divide);"
],
"challengeType":1
},
{
"_id":"bh1111c1c11feddfaeb4bdef",
"name":"Creating Decimals",
"dashedName":"waypoint-creating-decimals",
"difficulty":"9.9815",
"description":[
"",
"in JavaScript we can can work with decimal numbers",
"These decal numbers are known as floats.",
"Let's create a float now called myFloat and give it a value"
],
"tests":[
"assert((function(){if(typeof(myFloat) != 'undefined' && typeof(myFloat) == 'number' && editor.getValue().match(/\\./g).length >=2){return(true);}else{return(false);}})(), 'myFloat should be a decimal point number');"
],
"challengeSeed":[
"//var ourFloat = 5.7",
"//Create a number with a decimal point here called myFloat",
"In JavaScript we can store lists or collections of data in what are called arrays",
"Arrays are distinguished by the <code> [ </code> and <code> ] </code> around the data. Each piece of data is separated be a <code> , </code>",
"Now let's create a new array called <code> myArray </code> with a <code> string </code> and a <code> number </code> with a <code> , </code> separating each one",
"Refer to the example if you get stuck",
""
],
"tests":[
"assert(typeof(myArray) == 'object', 'myArray should be an array');",
"assert(typeof(myArray[0]) !== 'undefined' && typeof(myArray[0]) == 'string', 'The fist item in myArray should be a string');",
"assert(typeof(myArray[1]) !== 'undefined' && typeof(myArray[1]) == 'number', 'The second item in myArray should be a number');"
],
"challengeSeed":[
"//var array = ['John', 23];",
"",
"var myArray = [];",
"",
"",
"(function(z){return(z);})(myArray);"
],
"challengeType":1
},
{
"_id":"bh1111c1c11feddfaeb7bdef",
"name":"Nesting Arrays",
"dashedName":"waypoint-nesting-arrays",
"difficulty":"9.98161",
"description":[
"",
"We are also able to create arrays within arrays. This technique is called <code>nesting</code>.",
"Let's now go create a nested array called <code>myArray</code>"
],
"tests":[
"assert((function(){if(typeof(myArray) !== 'undefined' && typeof(myArray) === 'object' && typeof(myArray[0]) !== 'undefined' && typeof(myArray) === 'object'){return(true);}else{return(false);}})(), 'myArray should contain at least one array');"
"Once an array has been created we can access the data we have stored in them using indexes",
"Indexes are written in the same way as bracket notation that we covered earlier",
"Example:",
"<code>",
"var array = [1,2,3];",
"array[0];//equals 1",
"var data = array[1];",
"</code>",
"Create a var called <code>data</code> and set it to equal the first value of <code>myArray</code>"
],
"tests":[
"assert((function(){if(typeof(myArray) != 'undefined' && typeof(data) != 'undefined' && myArray[0] == data){return(true);}else{return(false);}})(), 'the variable data should equal the first value of myArray');"
"We are able to modify the data store in an array be using indexes",
"Example:",
"<code>",
"var ourArray = [1,2,3];",
"ourArray[0] = 3;//ourArray equals [3,2,3]",
"</code>",
"Now Let's modify <code>myArray</code> using an index",
""
],
"tests":[
"assert((function(){if(typeof(myArray) != 'undefined' && myArray[0] == 3 && myArray[1] == 2 && myArray[2] == 3){return(true);}else{return(false);}})(), 'myArray should now be [3,2,3]');",
"assert((function(){if(editor.getValue().match(/[0]/g).length >= 2 && editor.getValue().match(/=/g).length >= 2){return(true);}else{return(false);}})(), 'You should be using indexes to modify the values in myArray');"
"When and array has been defined we still have the ability to make changes to it afterwards",
"One common way in which we can manipulate the data in an array is through <code> .pop() </code>",
"<code> .pop() </code> is used to \"pop\" a value from the end of an array. We can retrieve this value by preforming the pop in a variable declaration.",
"any type of variable can be \"popped\" from and array",
"Let's try <code> .pop() </code> now"
],
"tests":[
"assert((function(d){if(d[0] == 'John' && d[1] == 23 && d[2] == undefined){return(true);}else{return(false);}})(myArray), 'myArray should only have the first two values left([\"John\", 23])');",
"assert((function(d){if(d[0] == 'cat' && d[1] == 2 && d[2] == undefined){return(true);}else{return(false);}})(removed), 'myArray should only have the first two values left([\"cat\"], 2)');"
],
"challengeSeed":[
"//var numbers = [1,2,3];",
"//console.log(numbers); //Gives [1,2,3]",
"//var removed = numbers.pop();",
"//console.log(numbers); //Gives [1,2]",
"//console.log(removed); //Gives 3",
"",
"var myArray = ['John', 23, ['cat', 2]];",
"var removed = _;//This should be ['cat', 2] and myArray should now be ['John', 23]",
"Another common way in which we can manipulate the data in an array is through <code> .shift() </code>",
"<code> .shift() </code> is used to \"shift\" a value from the start of an array. We can retrieve this value by preforming the shift in a variable declaration.",
"Let's try <code> .shift() </code> now"
],
"tests":[
"assert((function(d){if(d[0] == 23 && d[1][0] == 'dog' && d[1][1] == 3 && d[2] == undefined){return(true);}else{return(false);}})(myArray), 'myArray should only have the first two values left([\"John\", 23])');",
"assert((function(d){if(d == 'John'){return(true);}else{return(false);}})(removed), 'Removed should contain \"John\"');"
],
"challengeSeed":[
"var myArray = ['John', 23, ['dog', 3]];",
"var removed = _;//This should be ['John'] and myArray should now be ['John', 23]",
"Now that we've learned how to <code> shift </code> things from the start of the array, we need to learn how to <code> unshift </code> stuff back to the start",
"Let's take the code we had last time and <code> unshift </code> this value to the end: <code> 'Paul' </code>"
"In JavaScript we can divide up our code into separate and reusable parts called functions",
"here's and example of a function",
"<code>",
"function functionName (a, b){",
" return(a + b);",
"}",
"</code>",
"our function can be called like this",
"<code>functionName();</code>",
"Let's try creating and calling a function now called <code>myFunction</code>"
],
"tests":[
"assert((function(){if(typeof(f) !== 'undefined' && typeof(f) === 'number' && f === 9){return(true);}else{return(false);}})(), 'Your function should return the value of a + b');"
],
"challengeSeed":[
"var a = 4;",
"var b = 5;",
"//Don not modify the above!",
"//Create a function called myFunction that adds a and b",
"",
"",
"",
"",
"//Don't modify this!",
"if(typeof(myFunction) != 'undefined'){",
"var f=myFunction(a,b);",
"(function(){return(f);})();",
"}"
],
"challengeType":1
},
{
"_id":"bg9998c9c99feddfaeb9bdef",
"name":"I Object!",
"dashedName":"waypoint-i-object",
"difficulty":"9.9822",
"description":[
"",
"A very important data type in javascript is the <code> Object </code>",
"<code> Objects </code> a similar to <code> arrays </code> except that instead of using indexes to access and modify their data, Objects have what are called <code> properties </code>",
"Here's a sample Object",
"<code>",
"var cat = {",
" \"name\": \"Whiskers\",",
" \"legs\": 4,",
" \"tails\": 1,",
" \"enemies\": [\"Water\", \"Dogs\"]",
"};",
"</code>",
"Objects are useful for storing data in a structured way or in a way that represents a real world object like a cat.",
"Let's try to make a Object that represents a dog called myDog!"
],
"tests":[
"assert((function(z){if(z.hasOwnProperty('name') && z.name != undefined && typeof(z.name) == 'string'){return(true);}else{return(false);}})(myDog), 'myDog should contain the property name and it should be a string');",
"assert((function(z){if(z.hasOwnProperty('legs') && z.legs != undefined && typeof(z.legs) == 'number'){return(true);}else{return(false);}})(myDog), 'myDog should contain the property legs and it should be a number');",
"assert((function(z){if(z.hasOwnProperty('tails') && z.tails != undefined && typeof(z.tails) == 'number'){return(true);}else{return(false);}})(myDog), 'myDog should contain the property tails and it should be a number');",
"assert((function(z){if(z.hasOwnProperty('friends') && z.friends != undefined && Array.isArray(z.friends)){return(true);}else{return(false);}})(myDog), 'myDog should contain the property friends and it should be an array');"
],
"challengeSeed":[
"//var ourDog = {",
"// \"name\": \"Camper\"",
"// \"legs\": 4",
"// \"tails\": 1",
"// \"friends\": ['everything!']",
"//};",
"",
"/* add the name(string), legs(number), tails(number) and friends(array) properties to myDog.",
"You can set them to whatever you want!*/",
"",
"var myDog = {",
" ",
"};",
"",
"(function(z){return(z);})(myDog);"
],
"challengeType":1
},
{
"_id":"bg9999c9c99feddfaeb9bdef",
"name":"Manipulating Objects",
"dashedName":"waypoint-manipulating-objects",
"difficulty":"9.9823",
"description":[
"",
"Now that we have an objects we need to know how to add and remove properties from it",
"Let's try getting a for loop to work by pushing values to an array"
],
"tests":[
"assert(editor.getValue().match(/for\\(/g), 'You should be using a for loop for this!');",
"assert.deepEqual(myArray, [0,1,2,3,4], 'myArray should equal [0,1,2,3,4]');"
],
"challengeSeed":[
"var myArray = [];",
"//Push the numbers 0-4 to myArray",
"",
""
],
"challengeType":1
},
{
"_id":"bh1111c1c11feddfaeb1bdef",
"name":"Looping with while",
"dashedName":"waypoint-looping-with-while",
"difficulty":"9.9825",
"description":[
"",
"Loops are a critical part of any program! The next few challenges",
"first we will be taking a look at the for loop",
"<code>",
"var ourArray = [];",
"var i = 0;",
"while(i < 5){",
" ourArray.push(i);",
" i++;",
"}",
"</code>",
"Let's try getting a for loop to work by pushing values to an array"
],
"tests":[
"assert(editor.getValue().match(/while\\(/g), 'You should be using a while loop for this!');",
"assert.deepEqual(myArray, [0,1,2,3,4], 'myArray should equal [0,1,2,3,4]');"
],
"challengeSeed":[
"var myArray = [];",
"//Push the numbers 0-4 to myArray",
"",
""
],
"challengeType":1
},
{
"_id":"bh1111c1c11feddfaeb2bdef",
"name":"Looping with do while",
"dashedName":"waypoint-looping-with-do-while",
"difficulty":"9.9826",
"description":[
"",
"Let's now take a look at the do - while loop",
"<code>",
"var ourArray = [];",
"var i = 0;",
"do{",
" ourArray.push(i);",
" i++;",
"}while(i<5);",
"</code>",
"A do - while has a very special difference when compared to the for and while loops. The do while loop is guaranteed to execute preform it's action once regardless of whether or not the condition inside the while is met!",
"Let's try getting a do - while loop to work by pushing values to an array"
],
"tests":[
"assert.deepEqual(myArray, [0,1,2,3,4], 'myArray should equal [0,1,2,3,4]');",
"assert((function(){if(editor.getValue().match(/do/g) && editor.getValue(/while/g).match()){return(true);}else{return(false);}})(), 'You should be using a do while loop for this!');"
