I'am trying to write an extension which uses Prolog. At the moment I
want to understand how I can access the active Document in Scheme. I
found the-buffer in a discussion. I tried to use it but got an unbound
variable error. Is there a module I need to load? Can anybody
give me a hint how to use tree_to_texmacs? What I need is to transform
the tree to a Prolog representation without losing the information on
the origanl tree, so that I can send back editing commands to texmacs.