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JavaScript Introduction to Programming Control Structures If/Else

Davide Pugliese
Davide Pugliese
4,091 Points
Posted by Davide Pugliese
Davide Pugliese
4,091 Points

Which state does name transits to when no name is provided in the prompt?

Hello, I would like to know in this video when we have:

name = prompt ("What's your name?");

if (name) {
       ...
}

which state does name transit to if no name is provided in the prompt: null or undefined?

I guess it should go to undefined since it was not assigned any value to it. Is it correct?

2 Answers

Valdas Japertas
Valdas Japertas
4,522 Points
Valdas Japertas
Valdas Japertas
4,522 Points

Neither. It gets a value of empty string (""). You can test this using Chrome's JavaScript console:

var username

username = prompt("What is your name?")

username

You will see that console will write "undefined" at first, but after the promt it will give the values of username as "".