Checking a Boolean inside of an if statement

Question

Today I've come across a problem in Javascript that I can't understand at all.

I have this code:

var status = false;
console.log(status, typeof status);
if (status) {
  console.log("status is true");
} else {
  console.log("status is false");
}

I expected it would not satisfy the if statement, since status is false. Moreover, it's a Boolean, not a String.

I was wrong. It returned "status is true", so status did satisfy the if statement.

I changed my code to specify a condition, not just the variable:

var status = false;
console.log(status, typeof status);
if (status == false) {
  console.log("status is false");
} else {
  console.log("status is not false");
}

Notice that I switched the output messages, since we're not checking the value of the variable itself, but checking if it's false or not.

I really started to panic when I read "status is not false" on the console. How can it be other thing than false?

What am I missing?

Use a different variable name, or put it all inside an IIFE, or use `const` instead of `var` (because `window.status` will always be a string, like `window.name`) — CertainPerformance, Feb 06 '19 at 10:35
I'm not sure why you're experiencing this. I tested your code and got the correct result. — Ryan Walls, Feb 06 '19 at 10:36
@RyanWalls If you paste and run the code on the top level, you'll experience it too. — CertainPerformance, Feb 06 '19 at 10:36
@CertainPerformance It looks like it was the name of the variable. I can't thank you enough. — Ender, Feb 06 '19 at 10:53

score -1 · Accepted Answer · answered Feb 06 '19 at 10:38

You are experiencing this because status is a reserved word in js. Use another variable name like stat and it will work just fine.

For more info

var stat = false;
if(stat){
    console.log("status is true");
} else {
    console.log("status is false");
}

Checking a Boolean inside of an if statement

1 Answers1