Loading collection data...
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.
The values undefined, null, NaN, 0, "" (the empty string) and of course 'false' are so-called "falsy" values. This means that upon being used in a boolean operation, they will convert to false. To some it seems intuitive, to others dumb and/or arbitrary. In the end, it is just how the JavaScript language works. You can find further information on the MDN website.
It says it takes a boolean, you don't need to validate the input.
I got errors when I tried to submit this solution, so maybe they fixed it?
I agree with you.
This comment is hidden because it contains spoiler information about the solution