In vi/vim is it possible to match if/endif in a non-standard language so you can toggle between them using %? I know that this feature is usually reserved for parentheses and braces but this particular language doesn't use them.
I can see, from reading around, that you can set regions via ":syntax region" but I'm not sure if that applies to this case.
I am not a vi user. I'm asking mainly for a colleague.