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.
I am confused bit here!
I mean, what exactly is happening in your code.
Is it only taking values which matches 'd' or all.
And why you are using join("").
BTW nice oneliner dear! ^^