User manual

Chapter 11: Other ESS features and tools 56
11 Other ESS features and tools
ESS has a few extra features, which didn’t fit anywhere else.
11.1 ElDoc
In ElDoc mode, the echo area displays function’s arguments at point. From ESS version
12.03, ElDoc is active by default in ess-mode and inferior-ess-mode buffers. To activate
it only in ess-mode buffers, place the following into your init file:
(setq ess-use-eldoc ’script-only)
[User Option]ess-use-eldoc
If ‘t’, activate eldoc in ess-mode and inferior-ess-mode buffers. If ‘’script-only’
activate in ess-mode buffers only. Set ess-use-eldoc to nil to stop using ElDoc
altogether.
[User Option]ess-eldoc-show-on-symbol
This variable controls whether the help is shown only inside function calls. If set
to ‘t’, ElDoc shows help string whenever the point is on a symbol, otherwise (the
default), shows only when the point is in a function call, i.e. after ‘’(’’.
[User Option]ess-eldoc-abbreviation-style
The variable determines how the doc string should be abbreviated to fit into mini-
buffer. Posible values are ‘nil’, ‘mild’, ‘normal’, ‘strong’ and ‘aggressive’. Please
see the documentation of the variable for more details. The default filter is ‘normal’.
Ess-eldoc also honors the value of eldoc-echo-area-use-multiline-p, which if set
to ‘nil’, will cause the truncation of doc string indifferent of the value of ess-eldoc-
abbreviation-style. This way you can combine different filter levels with the truncation.
11.2 Handy commands
[Command]ess-handy-commands
Request and execute a command from ess-handy-commands list.
[User Option]ess-handy-commands
An alist of custom ESS commands available for call by ess-handy-commands and
ess-smart-comma function.
Currently contains:
change-directory
ess-change-directory
help-index ess-display-index
help-object
ess-display-help-on-object
vignettes ess-display-vignettes
objects[ls] ess-execute-objects