What is the difference between lexical scope and block scope?

Can you explain the difference between lexical scope and block scope?

Sure! Lexical scope refers to the visibility of variables based on their location within the source code, while block scope restricts variable visibility to the block in which they are defined, such as within curly braces.

Can you give me an example of each?

Of course! In JavaScript, a variable declared with let or const inside a block (like an if statement) has block scope. In contrast, a variable declared with var is function-scoped, meaning it can be accessed anywhere within the function it was declared in.

Why is lexical scope important?

Lexical scope is important because it helps maintain a clear structure in your code, allowing for better readability and predictability in variable access.

Are there any languages that don't use lexical scope?

Most modern programming languages, like JavaScript, Python, and Ruby, use lexical scope. However, some older languages or specific implementations may not follow this principle.