auto-complete sources for emmet-mode's snippets
First, ensure auto-complete and emmet-mode are installed: I recommend
using packages from Melpa.
You'll need both auto-complete and emmet-mode to be enabled and
working, so please consult the corresponding documentation is you have
any trouble with this.
Next, installac-emmet. If you choose not to use the convenient
package in Melpa, you'll need to add the directory containing
ac-emmet.el to your load-path, and then (require 'ac-emmet).
ac-emmet provides an emmet-specific completion source,
so auto-complete needs to be told to use them when ac-emmet is
active. To do this, put the following code in your emacs init file to
(require 'ac-emmet) ;; Not necessary if using ELPA package
(add-hook 'sgml-mode-hook 'ac-emmet-html-setup)
(add-hook 'css-mode-hook 'ac-emmet-css-setup)
ac-emmet should now automatically be enabled when you visit a buffer
in which emmet-mode is active and auto-complete is enabled. (The
symbols "Emmet and "AC" should appear in the modeline.)