Emacs tab auto-complete for R data.table?

Question

Anyone know how to get auto-complete working in Emacs for R data.tables (ess-mode)?

For example when I type tab below I'd like autocomplete to add "alpha"

DT <- data.table(alpha = 1:5)
DT[<type tab here>

thanks, jason

Answer 1

If you don't mind typing one more charactor, you can use 'Meta - /' after 'DT[a'