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.
Small nitpick. You shouldn't assume that the object will preserve insertion order.
In this case you could save the values in an array, and then build a lookup.
It's pretty well step to use regexp match into
fromRoman, it may be simplified a bit torom.match(/CM|CD|XC|XL|IX|IV|\w/gi)