JuniorTheoryCommon

What does the program print?

JavaScript

function show() {
    console.log(x);
    var x = 5;
}

show();

undefined

Expecting ReferenceError, as with let: a var exists in the whole function from its first line, holding undefined until var x = 5 runs.
Expecting 5, as if the whole line moved up: only the variable exists early, and the value 5 is assigned when its own line runs.

What does the program do if var x = 5 is replaced with let x = 5?
Can a function declared with function be called on a line above its declaration?

JuniorTheoryCommon

JavaScript

function show() {
    console.log(x);
    var x = 5;
}

show();

undefined

Expecting ReferenceError, as with let: a var exists in the whole function from its first line, holding undefined until var x = 5 runs.
Expecting 5, as if the whole line moved up: only the variable exists early, and the value 5 is assigned when its own line runs.

What does the program do if var x = 5 is replaced with let x = 5?
Can a function declared with function be called on a line above its declaration?