[ESS] customizing ess-smart-S-assign-key

[zenlines at gmail.com]

Hi List,

I would like to customize the ess-smart-S-assign-key to have act when I 
press _ twice, but can't get there.

I have looked through the ess-custom.el and ess-s-l.el and did not succeed.
Below doesn't work:

(require 'ess-site)
(setq ess-smart-S-assign-key "__")
(ess-toggle-S-assign nil)
(ess-toggle-S-assign nil)

I have been voice coding (now alternating) and needed to deactivate the 
nice functionality...

Thanks!
Brian

Ubuntu 12.04
emacs 24.3.1
ess-version: 13.09
Revision: 5778
Last Changed Date: 2013-09-27