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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.
throw an error- thats itthrowin error doesn't work for JavaScript. Tried different variants, but it didn't work. Specify what kind of error you want to be thrown!
Description too poor!
Then, your code mutated the input, as simple as that.
Passes all tests in JavaScript except for the mutation test case.