why make a wrong description of the kata? You could just write, remove all the spaces and $ and turn it into a double. If examples like " -$$30 $$$20 $2$ "

Cool: using toDoubleOrNull instead of catching the exception
Not so much: Two replace passes instead of one with a regex

You're right. Some warriors (and so do I) did this kata on December, so that is the reason why it worked :)

Read the description thoroughly and you'll see why it's solved as is :-)

this is not your month) I'm sorry) but if you interested it you can read about class date and his another functions

I think this solution only works for one month of the year. It certainly fails for me.