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JavaScript JavaScript Foundations Functions Return Values

antonio ortiz
antonio ortiz
2,059 Points
Posted by antonio ortiz
antonio ortiz
2,059 Points

I keep getting 'You're not checking if 'undefined' is being passed in'....

This is my code...

        function arrayCounter(array){
        if(array){
           return array.legnth;
        }else{
          return 0 === '' && !NaN || undefined;
    }

}

3 Answers

John W
John W
21,558 Points

Hmmm... your syntax is way off. Looks like you have some fundamental misunderstanding of the if/else syntax and type-checking. All the answers you need to fix it are available in this single video:

http://teamtreehouse.com/library/javascript-foundations/variables/null-and-undefined

antonio ortiz
antonio ortiz
2,059 Points
antonio ortiz
antonio ortiz
2,059 Points

Hey thanks John, You're right! As I looked back at the video I see now how 'type checking' was the theme however it doesn't come across really in the question.

This is what seems to get you passed the challenge...

 function arrayCounter(array) {
    if (typeof array === "string") {
      return 0;
    } else if (typeof array === "number") {
      return 0;
    } else if (typeof array === "undefined") {
      return 0;
    } else {
      return array.length;

What I found interesting was when I punched in 

typeof 'undefined';

in the console it spits back string? And shouldn't !NaN be better suited instead of 'number' and wouldn't it be undefined without quotes?

I appreciate your help!

antonio ortiz
antonio ortiz
2,059 Points
antonio ortiz
antonio ortiz
2,059 Points

Hey thanks John, You're right! As I looked back at the video I see now how 'type checking' was the theme however it doesn't come across really in the question.

This is what seems to get you passed the challenge...

 function arrayCounter(array) {
    if (typeof array === "string") {
      return 0;
    } else if (typeof array === "number") {
      return 0;
    } else if (typeof array === "undefined") {
      return 0;
    } else {
      return array.length;

What I found interesting was when I punched in 

typeof 'undefined';

in the console it spits back string? And shouldn't !NaN be better suited instead of 'number' and wouldn't it be undefined without quotes?

I appreciate your help!