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Collections are a way for you to organize kata so that you can create your own training routines. Every collection you create is public and automatically sharable with other warriors. After you have added a few kata to a collection you and others can train on the kata contained within the collection.
Get started now by creating a new collection.
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I got confused at the end here.
return xs.length ? xs.join(", ") + " & " + x : x || ""
I know in ES6, after ":" it is equal to "else return"; But I got confused with the "||". I know it meant "or" but how does the function knows that which option to choose between x or "" ?
So confused.