I was toying with the number object and I came up with this code (I know this is not good practice):

Number.prototype.times = function (evalString) {
  for (let i = 0; i < this; i++) {
    eval(evalString);
  }
}
//var someVar= 3;
(8).times("alert('kek')");

and it seems to work only when the someVar variable is not mented out, otherwise it throws the error in the title.

What causes this behavior?

I was toying with the number object and I came up with this code (I know this is not good practice):

Number.prototype.times = function (evalString) {
  for (let i = 0; i < this; i++) {
    eval(evalString);
  }
}
//var someVar= 3;
(8).times("alert('kek')");

and it seems to work only when the someVar variable is not mented out, otherwise it throws the error in the title.

What causes this behavior?

• javascript

1 Answer 1

Placing (...) immediately after a function expression (function (evalString) { … }) will call the function with the arguments you specify.

This is why depending on automatic semicolon insertion is not remended. Always end your statements with a ;.