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JavaScript

Damian Loyola
Damian Loyola
9,315 Points
Posted by Damian Loyola
Damian Loyola
9,315 Points

is this loop syntax valid in JS??

for(var i=0; i <10; i++){
}

i have seen in the javascript videos that the teacher use i+=1 , is i++ valid too? or im just confusing with other programming language?

4 Answers

Steven Parker
Steven Parker
229,732 Points
Steven Parker
Steven Parker
229,732 Points

Yes, JavaScript implements this operation.

In fact, JavaScript implements a unary increment prefix ("++i") and a unary increment postfix ("i++") along with the addition assignment ("i+=1") operator. In a stand-alone context like this they all do the same thing as "i = i + 1".

But be aware that the postfix operator is not quite the same as the others. If you do something that makes use of the value of the operation, the postfix returns the value before the increment:

let i = 3;
console.log(i++); 
// the value of "i" will be 4 here, but the log will show 3
jacobproffer
jacobproffer
24,604 Points
jacobproffer
jacobproffer
24,604 Points

Hey Damian,

This is valid JavaScript.

If you log i, you'll see 0 through 9.

Thomas Nilsen
Thomas Nilsen
14,957 Points
Thomas Nilsen
Thomas Nilsen
14,957 Points 
var i = 0

//These two are exactly the same
i++;
i += 1
Damian Loyola
Damian Loyola
9,315 Points
Damian Loyola
Damian Loyola
9,315 Points

thank you all, very clear answers :D