How to stop emacs from replacing underbar with <- in ess-mode

Question

ess-mode is \"Emacs speaks statistics.\" This mode is useful for editing programs for R or Splus (two separate statistics packages).

In my buffer, when

Answer 1

From ESS's manual (look under "Changes/New Features in 5.2.0"):

ESS[S]: Pressing underscore ("_") once inserts " <- " (as before); pressing underscore twice inserts a literal underscore. To stop this smart behaviour, add "(ess-toggle-underscore nil)" to your .emacs after ess-site has been loaded