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JavaScript JavaScript Foundations Functions Return Values

Caroline Rawson
Caroline Rawson
2,174 Points
Posted by Caroline Rawson
Caroline Rawson
2,174 Points

Javascript foundations, Functions, Return values challenge

I am getting an error for the Return Values challenge and I don't understand why.

Here's my code:

    function arrayCounter (function_array) {
        if (function_array.isArray){
        return function_array.length;
        }
        if (typeof function_array === ('string' | 'number' | 'undefined')) {
        return 0;
        }
      }

I am getting the following error: Bummer! You're not checking if 'undefined' is being passed in

Why is my check for undefined not working?

thanks!

Caroline Rawson
Caroline Rawson
2,174 Points
Caroline Rawson
Caroline Rawson
2,174 Points

Ok I realised that my OR operators were incorrect...

My use of isArray() was also incorrect - so I guess the first bit of code was being ignored and that's why the error related to the checking of undefined, which threw me a bit! Fixed these and now it's working :-)

My answer:

    function arrayCounter (function_array) {
    if (Array.isArray(function_array)){
        return function_array.length;
        }       
  if (typeof function_array === 'string' || typeof function_array === 'number' || typeof function_array === 'undefined') {
        return 0;
        }
      }
Adam Sackfield
Adam Sackfield
Courses Plus Student 19,663 Points

Great that you found the solution yourself. For future ref i found another post here with the same question answered link