Scope of variables

---

examples/js/scope.html

<script src="scope_bare.js"></script>
<script src="scope_var.js"></script>
<script src="scope_let.js"></script>
<script src="scope_const.js"></script>

examples/js/scope_bare.js

x = 1;


{
    console.log(`inside before: ${x}`);
    x = 2;
    console.log(`inside after: ${x}`);
}

console.log(`outside: ${x}`);

examples/js/scope_var.js

var x = 3;


{
    console.log(`inside before: ${x}`);
    var x = 4;
    console.log(`inside after: ${x}`);
}

console.log(`outside: ${x}`);

examples/js/scope_let.js

let x = 5;

console.log(`before: ${x}`);

{
    //console.log(`inside before: ${x}`); // Uncaught ReferenceError: Cannot access 'x' before initialization
    let x = 6;
    console.log(`inside after: ${x}`);
    x = 7;
    console.log(`inside end: ${x}`);

}

console.log(`outside: ${x}`);

examples/js/scope_const.js

const z = 10;

console.log(`before: ${x}`);

{
    console.log(`inside before: ${x}`);
    const z = 11;
    console.log(`inside after: ${x}`);
    z = 12; // Uncaught TypeError: 
    // console.log(`inside end: ${x}`);

}

console.log(`outside: ${x}`);