scope-discussion.md

Scopes Discussion

1. What is the scope of variable GLOBAL_DATA in the example below:

<script>
    let GLOBAL_DATA = {value : 1};
</script>

Pretend in the console, that we type:

console.log(GLOBAL_DATA);

2. What is the scope of variable x in the examples below:

let x = 1; // global
{
    let x = 2; //local
}
console.log(x); //1

var x = 1; // global
{
    var x = 2; // global
}
console.log(x); //2

3. What is the scope of variable x in the examples below:

function outerFn() {
    let x = 1;

    function log() {
        console.log(x);
    };

    function run(fn) {
        let x = 100;
        fn();
    }

    run(log);
};
outerFn(); //1

4. What do we call this method of scoping:

let x0 = 0;

function fn1() {
    let x1 = 1;
    fn2();

    function fn2() {
        let x2 = 2;
        fn3();

        function fn3() {
            let x3 = 3;
            console.log(x0 + " " + x1 + " " + x2 + " " + x3);
        };
    };
};
fn1();//0 1 2 3

5. What is the difference between global scope and other scope types and when do we use the global scope?

6. What is the difference between let and var defining a variable?

7. What is the difference between strict mode and sloppy mode?

ROOM 5
ali ibrahim, noor ridha, nma shawkat, zoriana Shatkovska

Q1: its A global SCOPE

Q2: the first example is local or function scope but the second one because it is declared with "var" will be a global variable.

Q3: its function scope.

Q4: Lexical

Q5: the global scope is the outermost scope, its variables can be accessed by the inner scopes like block scope and functional scope.

Q6: the var declaration declares the variable globally regardless of the block scope but the let declaration allows to declaration of variables that are limited to the scope or the block statement.

Q7: in the strict mode for example if you intentionally or unintentionally make a mistake in a code it can't be run but for sloppy mode, it can be run