JavaScript Truthy and Falsy Tutorial on Codecademy

Question

JavaScript Truthy and Falsy Tutorial on Codecademy

Could someone kindly clarify why this code is not functioning correctly?

let defaultName;
if (username) {
  defaultName = username;
} else {
  defaultName = 'Stranger';
}

This code snippet was found in the JavaScript section on Codecademy, but an error stating that 'username' is not defined keeps popping up.

Appreciate any insights or assistance. Thank you.

javascript

Answer 1

Answer №1

Attempting to assign the value of "username" to "defaultName" without declaring "username" first may seem amusing, but in JavaScript, values are assigned from right to left. So in your code:

let defaultName;
if (username) {
  defaultName = username;
...

This segment is incorrect because it instructs the program to assign "username" to "defaultName", which does not exist.

To make this code work, you need to initialize the "username" variable like this:

let username = 'John';
let defaultName;
if (username) {
  defaultName = username;
} else {
  defaultName = 'Stranger';
}

However, this is a simplistic example as in a real application, you would typically retrieve the username from a form, database, or through authorization, such as:

...
const user = this.props.auth.user;
let defaultName;
if (user) {
   defaultName = user.username;
} else {
   defaultName = 'Stranger';
}
...

In a scenario involving React, you might use a ternary operator for this function, although that is a more advanced topic.

Answer 2

Attempting to assign the value of "username" to "defaultName" without declaring "username" first may seem amusing, but in JavaScript, values are assigned from right to left. So in your code:

let defaultName;
if (username) {
  defaultName = username;
...

This segment is incorrect because it instructs the program to assign "username" to "defaultName", which does not exist.

To make this code work, you need to initialize the "username" variable like this:

let username = 'John';
let defaultName;
if (username) {
  defaultName = username;
} else {
  defaultName = 'Stranger';
}

However, this is a simplistic example as in a real application, you would typically retrieve the username from a form, database, or through authorization, such as:

...
const user = this.props.auth.user;
let defaultName;
if (user) {
   defaultName = user.username;
} else {
   defaultName = 'Stranger';
}
...

In a scenario involving React, you might use a ternary operator for this function, although that is a more advanced topic.

JavaScript Truthy and Falsy Tutorial on Codecademy

Answer №1

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