Rstudio has a great code completion feature. It provides a quick view of functions that start with a given string, as well as function and parameter definitions.
ESS is powerful enough, familiar to me, and integrated into Emacs, where I conduct most of my work - so I am hesitant to move, but this feature is making me consider such a move.
Is it possible to integrate this feature into Emacs ESS?
Is there anything similar to this for Emacs ESS?
Any hope that there will be (and if so, how could I support such an effort?)
You do get the completion thanks to the rcompgen package by Deepayan (now "promoted" into base R as part of the utils package). So when I type
lm(
and hit TAB a new buffer opens which gets me the left-hand side of your window above: the available options to the function at hand. I don't think you can show the help directly though.
There is / was also a way to get context-sensitive help in the mini-buffer when typing but I have forgottten how/where that gets turned on.
[EDIT: This is an old answer and auto-complete package dropped out of fashion since then. Please use company-mode instead. It should work by default. Wiki configuration entry is here.]
Recent versions of ESS (> v.12.02) integrate with auto-complete package out of the box (you need not configure anything, just install auto-complete). It provides help on arguments as well as function help. I added detailed instructions to the wiki
Ess-eldoc was also rewritten and from v.12.02 it's active by default, so you don't need to configure anything.
Or maybe we should all use search:
Emacs autocomplete-mode extension for ESS and R
I don't want to be grumpy, I found this few hours ago and I'm still shocked. It works like a charm. Though I still prefer the old-style pop-ups. =)
来源：https://stackoverflow.com/questions/6865344/is-it-possible-to-get-code-completion-for-r-in-emacs-ess-similar-to-what-is-avai