For efficiency you should you GOTO, so you can join trees that end up in same position.

Like those create your own adventures books.

True, but var and let are not same in js, so there is three.

if(true) {

var a = "dumdum"

}

console.log(a)

Is valid and functioning javascript. With let it is not.

C# has const string a = “Hello, World”;

var in js is legacy, and default should be let, but changing that would break everything