Question on Intro to Programming If/Else - Truthy or Falsy Results

Question

Hi There. On the "Intro to Programming Course" i'm struggling with a concept. What should probably be a simple question i'd imagine.

This is my code.

console.log("Before");

var name = prompt("What is your name");

if (name) { console.log("If block"); } else { console.log("Else block"); }

console.log("After");

When i execute the code and enter a name it returns the if block result which is expected as the (name) value is truthy. However when i enter something like false or 0 as my name it still comes back with "if block". The only time it comes back with the else is if i leave it blank (which is like null). Isn't it supposed to come back with the else block if I type in false or 0 or something falsy?

Thanks a bunch.

Answer 1 · 2014-01-25T20:49:39Z

January 25, 2014 8:49pm

The prompt() method always returns a string. For example, when you type

into the prompt box, the string "0" is returned rather than the number 0. So once the input from the prompt box is received,

name = " 0 ";

rather than

name = 0 ;

And the string "0" is truthy.

Answer 2 · 2014-01-25T20:53:19Z

January 25, 2014 8:53pm

Ahhh got it. Prompt always returns a string. Thanks!

Welcome to the Treehouse Community

Looking to learn something new?

Joel K

Joel K

Question on Intro to Programming If/Else - Truthy or Falsy Results

2 Answers

Gary Mann

Gary Mann

Joel K

Joel K