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JavaScript JavaScript Foundations Functions Return Values

Andy Durette
Andy Durette
31,183 Points
Posted by Andy Durette
Andy Durette
31,183 Points

JavaScript Functions Question

I am wondering why my code here 

  function arrayCounter (x) {
        if (typeof x !== 'array'){
         return 0;
      }else
        return x.length;
      }

Will not pass this JavaScript challenge http://teamtreehouse.com/library/return-values

However this JavaScript will

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

Doesn't the two code blocks do the same thing since I set that if the typeof was not equal to array it should return 0.

1 Answer

Alexander Costa
Alexander Costa
11,464 Points
Alexander Costa
Alexander Costa
11,464 Points

typeof thinks of arrays as objects

other wise your code says "if type of x is not a an array return 0" which would not work because like the second code suggests we are looking for typeof undefined, string, and number.