"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>",
"assert(editor.getValue().match(/(\\/\\*)...../g), 'Make sure you have at least one \/\\* \\*\/ style comment that has 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"
"Now, use the <code>var</code> keyword to create a <code>variable</code> called <code>myName</code>. Set its value to your name.",
"<code>Variables</code> are used to store values.",
"The name variable comes from the fact that it's value, varies!",
"Now Let's create our first variable called myName and because it's a name let's make it a string!",
"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.",
"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",
"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."
"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');"
"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');"
"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');"
"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');"
"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');"
"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",
"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>"
"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');"
"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');"
"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!');"
"assert(typeof(myFunction()) == 'number', 'The result of myFunction should be a number');",
"assert(editor.getValue().match(/Math.random/g), 'You should be using Math.random to create a random number');",
"assert(!(''+myFunction()).match(/\\./g), 'You should have multiplied the result of Math.random but 10 to make it a number that\\'s greater then zero');",
"assert(editor.getValue().match(/Math.floor/g), 'You should use Math.floor to remove the decimal part of the number');"
"We can use a certain mathematical expression to get a random number between between twp numbers.",
"<code>Math.floor(Math.random() * (max - min + 1)) + min</code>",
"By using this we can control the output of the random number.",
""
],
"tests":[
"assert(myFunction() >= min, 'The random number that\\'s generated by myFunction should be greater than or equal to the minimum number');",
"assert(myFunction() <= max, 'The random number that\\'s generated by myFunction should be less than or equal to the maximum number');",
"assert((function(){if(editor.getValue().match(/max/g).length >= 2 && editor.getValue().match(/min/g).length >= 3 && editor.getValue().match(/Math.floor/g) && editor.getValue().match(/Math.random/g)){return(true);}else{return(false);}})(), 'You should be using the function given in the description to calculate the random in number in a range');"
],
"challengeSeed":[
" var min = 0;",
" var max = 12;",
"function myFunction(){",
" //Make myFunction return a random number between zero and nine instead of a float",
"We can use if statements in JavaScript to only execute code if a certain condition is met",
"if statements require some sort of boolean condition evaluate",
"Example:",
"<code>if(1==2){",
" return(true);",
"}",
"else{",
" return(false);",
"}</code>",
"Let's have a go of using if statements now by making a coin-flip game",
"Create an if else statement to return <code>heads</code> if the flip var is zero and to return <code>tails</code> if it's not"
],
"tests":[
"assert((function(){if(myFunction() == 'heads' || myFunction() == 'tails'){return(true);}else{return(false);}})(), 'myFunction should either return heads or tails');",
"assert(editor.getValue().match(/if/g).length >= 3, 'You should have created a new if statement');",
"assert(editor.getValue().match(/else/g).length >= 2, 'You should have created a new else statement');"
"RegEx is a powerful tool we can use to find certain words or patterns in strings",
"RegEx can look difficult at first but there's not much to getting it working",
"If we wanted to find the number of times the word \"the\" occured in the string \"The dog chased the cat\" We could use the following RegEx:",
"<code>\/the+\/gi</code>",
"Let's break this down a bit",
"\"The\" is the pattern we want to match",
"\"+\" means we are looking for one or more occurrences of this pattern",
"\"g\" means that it searhces the whole string",
"\"i\" means that we are ignoring the case(upper or lower) of what we are looking for",
"Let's try finding the word and in the string \"John and Alan went to the shop and got some milk\" by replacing the <code>.+</code> in the currnet RegEx with something that will find the word \"and\" and count how many times it occurs"
],
"tests":[
"assert(test==2, 'You\\'re RegEx should have found two occurances of the word \"and\"');",
"assert(editor.getValue().match(/\\/and\\+\\/gi/), 'You should have used this RegEx to find the word \"and\"');"
],
"challengeSeed":[
"var test = (function(){",
" var testString = \"John and Alan went to the shop and got some milk\";",
