eval()

console.log(eval("2 + 2"));
// Expected output: 4

console.log(eval(new String("2 + 2")));
// Expected output: 2 + 2

console.log(eval("2 + 2") === eval("4"));
// Expected output: true

console.log(eval("2 + 2") === eval(new String("2 + 2")));
// Expected output: false

eval(new String("2 + 2")); //    String,  "2 + 2"
eval("2 + 2"); //  4

var expression = new String("2 + 2");
eval(expression.toString());

function test() {
  var x = 2,
    y = 4;
  console.log(eval("x + y")); //  ,    ,  - 6
  var geval = eval;
  console.log(geval("x + y")); //  ,    ,  ReferenceError, .. `x` -  
}

var obj = { a: 20, b: 30 };
var propname = getPropName(); //  "a"  "b"

eval("var result = obj." + propname);

var obj = { a: 20, b: 30 };
var propname = getPropName(); //  "a"  "b"
var result = obj[propname]; //  obj[ "a" ]  ,   obj.a

//  setTimeout(" ... ", 1000) :
setTimeout(function() { ... }, 1000);

//  elt.setAttribute("onclick", "...") :
elt.addEventListener("click", function() { ... } , false);

var x = 2;
var y = 39;
var z = "42";
eval("x + y + 1"); //  42
eval(z); //  42

var x = 5;
var str = "if (x == 5) {console.log('z is 42'); z = 42;} else z = 0; ";

console.log("z is ", eval(str));

var str = "if ( a ) { 1+1; } else { 1+2; }";
var a = true;
var b = eval(str); //  2

console.log("b is : " + b);

a = false;
b = eval(str); //  3

console.log("b is : " + b);

var fctStr1 = "function a() {}";
var fctStr2 = "(function a() {})";
var fct1 = eval(fctStr1); //  undefined
var fct2 = eval(fctStr2); //