JavaScript ++ Operator | X++ and X = X++ Explanation

JavaScript ++ operator, javascript increment operator, increment operator in javascript, increment and decrement operators in javascript with examples, javascript decrement operator, JavaScript ++, javascript operator

var x = 10;
var x = x++;
var x = ++x;
console.log(x);
*output*
11

var x = 10;
var x;
var x = ++x;
console.log(x);

*output*
11   (If you are not clear, dont worry, we will explain this in this post as well)

var x = 10;
var y = x++;
var z = ++x;
console.log(x,y,z);

12 10 12

var x = 10;
var x = undefined;
var x = ++x;
console.log(x);

NaN

var x = 10;
var x = ++x;
var x = x++;
console.log(x);

11

var x = 10;
var x = ++x;
var x = x++;
var y =x;
console.log(x);
console.log(y);

11 11

var x = 99;
x = x++;
console.log( x );

99

var x = 10;
var x = ++x;
var x = x++;
var x = x++;
var x = x++;
var y =x;
console.log(x);

11

var x = 10;
var x = ++x;
var x = x++;
var x = ++x;
var x = x++;
var y =x;
console.log(x, y);

12 12

— — -I am sure that you all will be confused on above questions and it’s output…

Confusion !!!!!

Let’s explain it in a simple way.

You probably learned that x++ is the same as x = x+1. Well, that’s not the whole story. x = x++ and simple x++ both are not same.

When we do var x = x++; it simply means we are doing var x = x nothing else. you’ve just set x back to its old value: !! It is not same as var x = x + 1;
But
When we do x++ only: it is same as x = x + 1;

Example :

var x = 10;
var x = x++;
console.log(x);

the value of x is still > 10;

var x = 12;
x++;
console.log(x);

// Now the value of x is 13.

Another important question. what will be the output for the below code?

var x = 0;
var loop = function(){
while(x < 3){
console.log(“I’m looping!”);
x= x++;
}
};

loop();

Think! Think !! Think !!

— — — — — –

— — –

— –

—

— –

And the answer is it will run as an infinite loop as per the above explanation.

Read more technical blogs – https://jsmount.com

javascript increment operator, increment operator in javascript, increment and decrement operators in javascript with examples, javascript decrement operator, JavaScript ++, javascript operator

JS Mount

Learn More

JavaScript ++ Operator | X++ and X = X++ Explanation

Confusion !!!!!

Let’s explain it in a simple way.

Another important question. what will be the output for the below code?

And the answer is it will run as an infinite loop as per the above explanation.

Leave a Reply Cancel Reply