JSFiddle - React, Tailwind, and code Playground

by alirokni

JavaScript

//http://www.adequatelygood.com/JavaScript-Scoping-and-Hoisting.html
var count = 1;
alert(count) // 1
if (true) {
    //       function alertMeAgain(){
    var count = 2;
    alert(count); //2
    //      };    
}
//alertMeAgain()
alert(count); //2, with function back to 1

//http://msdn.microsoft.com/en-us/library/ie/bzt2dkta(v=vs.94).aspx
var aNumber = 100;
tweak();

function tweak() {
    // This prints "undefined", because aNumber is also defined locally below.
    alert(aNumber);
    if (false) {
        //(function(){ // to make it execute and set the value to 100
        var aNumber = 123;
        //})()  
    }
}

var name = "Richard";

function showName() {
    var name = "Jack"; // local variable; only accessible in this showName function
    alert(name); // Jack
}
alert(name); // Richard: the global variable

// Finally it is 
var count = 0;
alert("1th " + count); // 0
//if (!count) {
var count = 1;
alert("2nd " + count); // 1
function test() { // closure
    var count = 0;
    return "3rd " + count; // 0
}
//}
alert("4th " + count); // 1
alert(test());