Why does this program output “11” in a loop when use var and with let if works?

Asked Mar 31 '18 at 19:08

Active Mar 31 '18 at 19:24

Viewed 43 times

Why output is 10 when use var and with let it works the loop. Edit the output is 11 but why let and var are different

var funcions = [];

for (var x = 0; x <= 10; x++) {
  funcions.push(function() {
    console.log(x);
  });
}

funcions.forEach(
  function(func) {
    func();
  }
);

I know that let, is a signal that the variable may be reassigned, such as a counter in a loop, or a value swap in an algorithm. It also signals that the variable will be used only in the block it’s defined in, which is not always the entire containing function.

edited Mar 31 '18 at 19:24

asked Mar 31 '18 at 19:08

Rene Israel Ibarra

1

Note: you actually get `11` since you are using `x <= 10` instead of `x < 10`. – Terry Mar 31 '18 at 19:10
By the time you execute each of the functions, x is 11. – Reinstate Monica Cellio Mar 31 '18 at 19:11
When using `var x`, `x` is not scoped to each iteration of the loop. – Terry Mar 31 '18 at 19:11
yes 11 sorry mm thank you – Rene Israel Ibarra Mar 31 '18 at 19:13
but I want why let vs var sorry I have a bad english – Rene Israel Ibarra Mar 31 '18 at 19:16

Why does this program output “11” in a loop when use var and with let if works?

0 Answers0