How does lexical scoping work in JavaScript?

Can you explain what lexical scoping is in JavaScript?

Sure! Lexical scoping refers to the way variable scope is determined in JavaScript. It means that a function's scope is defined by its location within the source code, and it can access variables from its own scope and any parent scopes.

Can you give me an example of lexical scoping?

Absolutely! Here's a simple example:

function outerFunction() {
    let outerVariable = 'I am outside!';
    function innerFunction() {
        console.log(outerVariable);
    }
    innerFunction();
}
outerFunction();

In this case, innerFunction can access outerVariable because of lexical scoping.

What happens if I try to access a variable from a different scope?

If you try to access a variable that is not in the current scope or any parent scope, JavaScript will throw a ReferenceError. For example, if innerFunction tried to access a variable defined only in another function, it wouldn't be able to.

Are there any exceptions to lexical scoping?

In JavaScript, lexical scoping is quite strict, but you can use techniques like closures to create functions that can access variables from their parent scopes even after the parent function has executed.