1-one-email.js

// Working with one email

const emailFromNatalie = {
    author: "Natalie",
    to: "Calvin",
    message: "Heyyyy",
    read: false
}

alert(emailFromNatalie.message)

2-array-of-emails.js

// Working with an array of emails (this variable and the array inside is used in the later examples)

const emailList = [
    {
        id: 234,
        author: "Natalie",
        to: "Calvin",
        message: "Heyyyy",
        read: false
    },
    {
        id: 1654,
        author: "Xee",
        to: "Calvin",
        message: "What's up?",
        read: true
    },
    {
        id: 474,
        author: "Dylan",
        to: "Calvin",
        message: "Good day",
        read: false
    }
]

alert( emailList[0].message )

3-for-loop-email-list-string.js

// Making a nice alert of the emails using a for loop
// !! Uses the emailList variable in array-of-emails.js !!

let emailListString = "";
for(let i = 0; i < emailList.length; i++) {
    emailListString += emailList[i].author + ": " + emailList[i].message + "\n";
}
alert(emailListString)

4-for-each-email-list-string.js

// Making a nice alert of the emails using for each
// !! Uses the emailList variable in array-of-emails.js !!

let emailListString = "";
function addToListString(email) {
    emailListString += email.author + ": " + email.message + "\n";
}
emailList.forEach(addToListString);

5-converting-from-normal-to-arrow.js

// The process of converting the normal function way into the more commonly used arrow function way
// !! Uses the emailList variable in array-of-emails.js !!

// Normal
function addToListString(email) {
    emailListString += email.author + ": " + email.message + "\n";
}
emailList.forEach(addToListString);

/* CAN BE CONVERTED TO */

// Arrow
const addToListString = (email) => {
    emailListString += email.author + ": " + email.message + "\n";
}
emailList.forEach(addToListString);

/* CAN BE CONVERTED TO */

// No curly brackets
const addToListString = (email) => emailListString += email.author + ": " + email.message + "\n";
emailList.forEach(addToListString);

/* CAN BE CONVERTED TO */

// No parenthesis
const addToListString = email => emailListString += email.author + ": " + email.message + "\n";
emailList.forEach(addToListString);

/* CAN BE CONVERTED TO */

// Passing in the function itself
// This is the way experienced developers tend to do it
emailList.forEach( email => emailListString += email.author + ": " + email.message + "\n" );

6-map-email-list-string.js

// Making a nice alert of the emails using map
// !! Uses the emailList variable in array-of-emails.js !!

const emailStringList = emailList.map( e => e.author + ": " + e.message );
alert( emailStringList.join("\n\n") );

7-find-email.js

// Finds an email with a particular id (or you could find it by author or whatever)
// !! Uses the emailList variable in array-of-emails.js !!

const emailFromNatalie = emailList.find( email => email.id === 1654 )
alert( emailFromNatalie.message );

8-filter-emails.js

// Filters emails and gives only the unread ones, then marks them all as read, then filters for unread again
// !! Uses the emailList variable in array-of-emails.js !!

let unreadEmails = emailList.filter( e => !e.read )
alert("You have " + unreadEmails.length + " unread emails");

// Set all emails as read
emailList.forEach( email => email.read = true );

unreadEmails = emailList.filter( e => !e.read )
alert("You have " + unreadEmails.length + " unread emails");