aaronfrost

let a = 0; 
if(true){
    let a = 2;
    console.log(“here a = “,a);
}
console.log(“at the end a = “,a);

aaronfrost

let foo = 0;
if(true){
     let bar = 1;
}
console.log( foo + bar );
//results in runtime error, bar is not defined

aaronfrost

var run = undefined;
run(); //error, since undefined isn’t a function
run = function(){
    console.log(“running”);
}
run();

aaronfrost

run();
var run = function(){
    console.log(“running”);
}
run();

aaronfrost

function run(){
    console.log(“running”);
}
run();
run();

aaronfrost

run();
function run(){
    console.log(“running”);
}
run();

aaronfrost

function run(){
    console.log(“running”);
}

aaronfrost

var a = 1;
 
function run(){
    var a = undefined;
    if(true){
        a = 2;
    }
}
run();
console.log(a);

aaronfrost

var a = 1;
 
function run(){
    if(true){
        var a = 2;
    }
}
run();
console.log(a);

aaronfrost

var foo = undefined;
var bar = undefined;
foo = 0;
if(true){
     bar = 1;
}
console.log( foo + bar );