console-1690434678979.log

var arr = [10,20,30,40,50];
undefined
for(let i = 0 ; i<arr.length; i++){
console.log(arr[i]);
}
VM228:2 10
VM228:2 20
VM228:2 30
VM228:2 40
VM228:2 50
undefined
arr.forEach;
ƒ forEach() { [native code] }
arr.forEach();
VM312:1 Uncaught TypeError: undefined is not a function
    at Array.forEach (<anonymous>)
    at <anonymous>:1:5
(anonymous) @ VM312:1
arr.forEach(console.log());
VM368:1 Uncaught TypeError: undefined is not a function
    at Array.forEach (<anonymous>)
    at <anonymous>:1:5
(anonymous) @ VM368:1
arr.forEach(function(e){
    console.log(e);
});
VM439:2 10
VM439:2 20
VM439:2 30
VM439:2 40
VM439:2 50
undefined
arr.forEach(function(e){
    console.log('E is ', e);
});
VM462:2 E is  10
VM462:2 E is  20
VM462:2 E is  30
VM462:2 E is  40
VM462:2 E is  50
undefined
arr.forEach(e=>console.log('E is ', e));
VM484:1 E is  10
VM484:1 E is  20
VM484:1 E is  30
VM484:1 E is  40
VM484:1 E is  50
undefined
var a= [[10,20],[30,40]];
undefined
a.forEach(e=>e.forEach(y=>console.log(y)));
VM687:1 10
VM687:1 20
VM687:1 30
VM687:1 40
undefined
arr;
(5) [10, 20, 30, 40, 50]
arr.findIndex(e=>e==30);
2
arr.filter(e=>e>=30);
(3) [30, 40, 50]
arr.filter(e=>e>=30).length;
3
arr.filter(function(e){
   return e>=30;
}).length;
3
var t = arr.filter(e=>true);
undefined
t;
(5) [10, 20, 30, 40, 50]
t== arr;
false
arr;
(5) [10, 20, 30, 40, 50]
arr = [10,20,30, 100,10,20,30,100,30,90];
(10) [10, 20, 30, 100, 10, 20, 30, 100, 30, 90]
arr = arr.filter(e=>e!=30)
(7) [10, 20, 100, 10, 20, 100, 90]
arr;
(7) [10, 20, 100, 10, 20, 100, 90]
arr.sort();
(7) [10, 10, 100, 100, 20, 20, 90]
arr.sort((a,b)=>a-b);
(7) [10, 10, 20, 20, 90, 100, 100]
arr.sort((a,b)=>b-a);
(7) [100, 100, 90, 20, 20, 10, 10]
var names = ["tim", "ram" ,"amit","shyam", "sohan"];
undefined
"tim" - "ram";
NaN
"tim".localeCompare("ram");
1
"ram".localeCompare("tim");
-1
"tim".localeCompare("tim");
0