Broken indentation. The project's indentation is awful, but let's at least not make it worse.

This file uses tabs and spaces to indent lines. Vim command line to switch to the right settings is `:set softtabstop=8 tabstop=8 shiftwidth=4 noexpandtab` (or shorter `:set sts=8 ts=8 sw=4 noet`). Csaba's indentation plugin (https://github.com/hcs42/vim-erlang-runtime) does wonders if used with the correct settings. I don't know how to make Emacs or others behave the right way, but I'm sure it's possible.

Alternatively, the whole file might be reindented to use just spaces. I suggest `:set sts=8 ts=8 sw=4 et` and Csaba's plugin again.