What is the difference between closures and lexical scope?

What is the difference between closures and lexical scope?

Closures are functions that remember their outer variables even when the function is executed outside its original scope. Lexical scope, on the other hand, refers to the visibility of variables based on their physical placement in the code.

Can you give me an example of a closure?

Sure! Here's a simple example:

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

const closureFunction = outerFunction();
closureFunction(); // Outputs: I am outside!

How does lexical scope work in this example?

In this example, innerFunction has access to outerVariable because of lexical scoping. It can access variables from its own scope and any outer scopes where it was defined.

Are closures always a good practice?

Closures can be very useful, but they can also lead to memory leaks if not managed properly. It's important to use them wisely.