Line 111, why is the variable shortUrl 'undefined' if it has just been defined above? Why isn't the variable global?

[jaimeggb]

Hi all

Please help

Line 111, why is the variable shortUrl ‘undefined’ if it has just been defined above? Why isn’t the variable global?

boilerplate-project-urlshortener

Thanks for your time

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User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.107 Safari/537.36

Challenge: URL Shortener Microservice

Link to the challenge:

freeCodeCamp.org

[jsdisco]

Does it log undefined or does it throw an Uncaught ReferenceError: shortURL is not defined ?
Do you see this log? console.log('2 ' + shortUrl)?

You’re using loose comparison here:

if (urlPairFound != null) {
  var shortUrl = urlPairFound.shortUrl; 
  console.log('2 ' + shortUrl);
}

console.log('3 ' + shortURL);

If urlPairFound is undefined instead of null, this statement will be false and it’ll skip the if block. So I’d first check if urlPairFound is undefined.

[jaimeggb]

Yes I see that log, as shown:

[lasjorg]

shortUrl and shortURL are not the same identifier.

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Edit: BTW, it’s not global it’s function scoped.

Can I ask why are you redeclaring the variable 4 times? Personally, I would not suggest doing that. If you want block scoped unique variables use let or const. Otherwise, declare the var variable one time and reassign its value.

[jaimeggb]

I managed to fix the problem

It consisted of two sub problems/mistakes

1. A typo: I had written ‘shortURL’ instead of ‘shortUrl’ which was what I had used earlier when I declared the variable

2. I was trying to use the ‘shortUrl’ variable OUTSIDE of the
   function(err, urlPairFound) {...}
   function, hence, the program had no clue what I meant by urlPairFound

Thanks for your time

Jaime