SOURCE

var foo ={n:1};
(function(foo){
console.log(foo.n);
foo.n=3;
var foo={n:2};
console.log(foo.n);
})(foo);
console.log(foo.n);

var bb;
console.log(bb, null==undefined)

var msg='hello'
for(var i=0;i<10;i++){
var msg = 'hello'+i*2+i;
}
console.log(msg)

console.log(typeof(123+''))

var color='green';
var test4399={
    color: 'blue',
    getColor: function(){
        var color='red';
        console.log(this.color)
    }
}

var getColor = test4399.getColor;
getColor();
test4399.getColor();

let arr=['abcd', 'ab', 'abc'];
arr.sort(function(a,b){
    return a.length - b.length
})
console.log(arr)

let str='str123 '
let strarr = Array.from(str);
console.log(isNaN(123))

console.log(str.indexOf(0))