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JavaScript

Posted by federico enrico
federico enrico
6,143 Points

Null and Undefined - Problem 

var myVar;

undefined = true;

console.log(typeof myVar === "undefined");
console.log(myVar === undefined);

this is my code, when I open it in the chrome console, instead of getting true-false, I get true-true anyway.

I can't understand why. Can anybody help?

1 Answer

Ivan Uvarov
Ivan Uvarov
22,403 Points
Ivan Uvarov
Ivan Uvarov
22,403 Points

What is this line supposed to do? Now it doesn't do anything. Do you have a typo?

undefined = true;

Now, you just create a new variable and don't assign any value to it. So myVar is undefined after executing your code. That's why value of myVar is undefined and type of this variable is "undefined".