Its because at the very end there are non letters that they expect us to deal with. I believe its a string of "-.-"

@d33con I am getting the same error? I will pass all the tests, but then on submitting it isn't passing ?

Okay, so after experimenting with my code. I realized I wasn't testing for upper case letters, nor was I returning a string in 'quotes'. Once I tested for this i passed.

Thank you. I had to feed '''empty_return''' into the nested function for my solution. Thanks for your explanations.

What happens to empty_return if you call nato twice? Try console.log(nato("a")); console.log(nato("b")). What's the expected output? What's your output? If you can answer all those questions, you should be able to fix your problem. Also, please use code blocks to post code. Either ``` backticks:

```javascript
function helloWorld(){
  return "Hello, world!";
}
```

Or indent your code by 4 spaces.

    function helloWorld(){
      return "Hello, world!";
    }

Good luck.

????

Ahem ;). That being said, you should provide more information. Which language, and what's your solution (mark as having spoiler content!)?

When I run my code on another ide it returns "BRAVO ALPHA BRAVO BRAVO LIME ECHO" , however when I run the code in through Kata's very own IDE it returns "BRAVO ALPHA BRAVO BRAVO LIME ECHO BRAVO ALPHA BRAVO BRAVO LIME ECHO" It doubles for reasons I can't understand????

Keeps returning "should work with zeros - Expected: 0, instead got: undefined", but I pass zeros and they are appropriately summed up. Not sure what is erroring ??

Thanks for sharing that tip. I found a really nice explanation of currying here: http://www.drdobbs.com/open-source/currying-and-partial-functions-in-javasc/231001821?pgno=2

'Lambda' refers to either a keyword in some languages or an actual construct. In javascript, there are no 'lambdas', just functions in lambda-calculus-like format. Therefore, no.

Does this excercise have to have a lambda function? I have passing by iterating over my arguments.length, but I am not using any lamda functions.

You should always add both the code and the language. Otherwise one cannot help you. (Don't forget to mark your post as spoiler)