Writing a custom fold expression

With a little bit of Vimscript, you can create a custom folding expression for any filetype. We'll start by looking at the mechanics of folding with markers, then go on to create a folding expression for markdown documents.

*On the 5th of December, I’m going to teach my [Vim Masterclass online][online]. It will run from 5pm GMT. That’s 9am if you live in San Fransisco, or 12 noon if you live in New York. Tickets cost £95, which is about US $150, and you can [purchase them from EventBrite][online].*

[online]: http://vimcasts-online-2.eventbrite.com/