📢 announcement*⚡⚡⚡⚡⚡
We are going to start delivering valuable content on Instagram.
Follow 👉 https://www.instagram.com/web_design_development_learn ( on Instagram)
Benefits:😉
You will get video, Tips and tricks... more learning stuff.
Follow us 👉 https://www.instagram.com/web_design_development_learn ( on Instagram )
*Don't forget to share with your friends*
Good bye 🤗
We are going to start delivering valuable content on Instagram.
Follow 👉 https://www.instagram.com/web_design_development_learn ( on Instagram)
Benefits:😉
You will get video, Tips and tricks... more learning stuff.
Follow us 👉 https://www.instagram.com/web_design_development_learn ( on Instagram )
*Don't forget to share with your friends*
Good bye 🤗
What will be the output? ( JavaScript )
console.log ( NaN !== NaN );
console.log ( NaN !== NaN );
Anonymous Quiz
35%
True
45%
False
20%
Error
Visit the website neumorphism.io to create awesome Neumorphism. It's super easy 😃.
🙏🙏🙏
Guys, we have a request to you. If you like our channel, please share with your friends or social media. Here is the link of our channel
http://t.me/WebsiteDesignLearningGroup
Guys, we have a request to you. If you like our channel, please share with your friends or social media. Here is the link of our channel
http://t.me/WebsiteDesignLearningGroup
function sayHi() { console.log(name);
console.log(age); var name = 'Lydia';
let age = 21; } sayHi();
console.log(age); var name = 'Lydia';
let age = 21; } sayHi();
Anonymous Quiz
34%
Lydia and undefined
18%
Lydia and ReferenceError
18%
ReferenceError and 21
30%
undefined and ReferenceError
What is output of the above code?
Anonymous Quiz
54%
0 1 2 and 0 1 2
28%
0 1 2 and 3 3 3
18%
3 3 3 and 0 1 2
Web design & 😃 development
function sayHi() { console.log(name);
console.log(age); var name = 'Lydia';
let age = 21; } sayHi();
console.log(age); var name = 'Lydia';
let age = 21; } sayHi();
🅰NSWER:
Within the function, we first declare the name variable with the var keyword. This means that the variable gets hoisted (memory space is set up during the creation phase) with the default value of undefined, until we actually get to the line where we define the variable. We haven't defined the variable yet on the line where we try to log the name variable, so it still holds the value of undefined.
Variables with the let keyword (and const) are hoisted, but unlike var, don't get initialized. They are not accessible before the line we declare (initialize) them. This is called the "temporal dead zone". When we try to access the variables before they are declared, JavaScript throws a ReferenceError.
Within the function, we first declare the name variable with the var keyword. This means that the variable gets hoisted (memory space is set up during the creation phase) with the default value of undefined, until we actually get to the line where we define the variable. We haven't defined the variable yet on the line where we try to log the name variable, so it still holds the value of undefined.
Variables with the let keyword (and const) are hoisted, but unlike var, don't get initialized. They are not accessible before the line we declare (initialize) them. This is called the "temporal dead zone". When we try to access the variables before they are declared, JavaScript throws a ReferenceError.