Question about 'Scope'

JavaScript
1

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My question about scope is: If a variable is outside of a function it is globally scoped, if it is inside a function it is locally scoped / block scope. what is the classification of a locally scoped variable at the top of the function code block and a variable in the if/else statements ?

2

There is more than just scope for a function and for a variable. For let and const, any set of {} creates a scope. For these variables, the scope is local to the containing {}.

function sumThese(lower, upper) {
  // upper, lower, and sum are  local to the function
  let sum = 0;

  for (let i = lower; i <= upper; i++) {
    // i is local to this loop
    sum += i;
  }
}

// These guys have global scope
let num1 = 5;
let num2 = 10;

console.log(sumThese(num1, num2));
3

1: what is the classification of a locally scoped variable at the top of the function code block
If it’s before the function it’s globally if it’s inside the function it’s locally

a variable in the if/else statements ?
If else is ussually in the function so localy

Also the local variable will overide the global one

4

Lexical scope is pretty simple: a variable has the scope of whatever pair of curly braces it’s in. That’s it. Variables declared deeper in will shadow those further out.

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