What is hoisting in JavaScript? Can you give me examples?

What is hoisting in JavaScript? Can you give me examples?

Hoisting is a JavaScript mechanism where variables and function declarations are moved to the top of their containing scope during compilation.

Can you show me an example of hoisting with variables?

Sure! For example:

console.log(x); // undefined
var x = 5;
console.log(x); // 5

In this case, the declaration of x is hoisted, but the assignment happens at runtime.

What about function hoisting?

Function declarations are also hoisted. For example:

console.log(myFunction()); // 'Hello!'
function myFunction() {
    return 'Hello!';
}

Here, myFunction can be called before its declaration.

Are there any differences between var, let, and const in hoisting?

Yes! var is hoisted and initialized to undefined, while let and const are hoisted but not initialized, leading to a ReferenceError if accessed before declaration.