Filename

Hi there, I understand that I can set the "slug" metadata to change the slug to something other than a slugified version of a post's title. Is there a way to just default to using the filename? For example, if the filename is 2015-04-05.pithy-slug.md And the title is # How to write pithy slugs in 17 steps or more! I would like the slug to be pithy-slug. Alex