Podcast
Questions and Answers
Which keyword is now preferred for variable declaration in JavaScript?
Which keyword is now preferred for variable declaration in JavaScript?
Where can a variable declared with var be accessed?
Where can a variable declared with var be accessed?
What is hoisting in JavaScript?
What is hoisting in JavaScript?
What is the scope of a variable declared with let?
What is the scope of a variable declared with let?
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Can a let variable be re-declared within its scope?
Can a let variable be re-declared within its scope?
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Study Notes
Variable Declaration in JavaScript
-
letis the preferred keyword for variable declaration in JavaScript.
Variable Scope with var
- A variable declared with
varcan be accessed from anywhere in the script, including outside the block it was declared in.
Hoisting in JavaScript
- Hoisting is a JavaScript mechanism where variable declarations are moved to the top of their scope, regardless of where they are actually declared.
- This means that a variable can be used before it is declared, but its value will be
undefineduntil it is actually declared.
Variable Scope with let
- The scope of a variable declared with
letis limited to the block it was declared in (e.g.,if,for,while,function, etc.).
RedDeclaring let Variables
- A
letvariable cannot be re-declared within its scope.
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Description
Test your knowledge of variable scope and hoisting in JavaScript with this quiz. Learn about the global scope of 'var' variables and how they differ from function-scoped variables. Explore the concept of hoisting and its impact on variable declaration and function definition.
