Read entire directory for a particular file type

[beberman]

I've been using this emacs plugin for a bit more than a year. Its great. Looking through the code it looks like the source text that is used for the suggestion code is a window in the current buffer. The performance would likely be better if it read all the code in a directory or in a file path set given a file extension. For example I'm using it with lisp and the ability to have it read a whole package in a single directory would help a lot.