[ESS] ess configured to invoke either R and R-devel?

[Martin Maechler]

>>>>> "PS" == Paul Shannon <pshannon at systemsbiology.org>
>>>>>     on Tue, 26 Jul 2011 09:38:17 -0700 writes:

    PS> I have just started to keep (and use) two versions of R
    PS> and Bioconductor -- the release, and the devel version.
    PS> How can I modify or adapt of invoke ess so that I run
    PS> the version I want?

Well, it depends..

If I type (in Emacs)  "M-x R [Tab]",
where "[Tab]" means to press the tab (tabulator) key,
I get

   Possible completions are:
   R 	R-1.0
   R-1.0.0 	R-1.0.1
   R-1.1 	R-1.1.0
   R-1.1.1 	R-1.2
   R-1.2.0 	R-1.2.1
   R-1.2.2 	R-1.2.3
   R-1.3 	R-1.3.0
   R-1.3.1 	R-1.4
   R-1.4.0 	R-1.4.1
   R-1.5 	R-1.5.0
   R-1.5.1 	R-1.6
   R-1.6.0 	R-1.6.1
   R-1.6.2 	R-1.7
   R-1.7.0 	R-1.7.1
   R-1.8 	R-1.8.0
   R-1.8.1 	R-1.9
   R-1.9.0 	R-1.9.1
   R-2-debian 	R-2.0.0
   R-2.0.1 	R-2.1.0
   R-2.1.1 	R-2.10.0
   R-2.10.1 	R-2.11.0
   R-2.11.1 	R-2.12.0
   R-2.12.1 	R-2.12.2
   R-2.13.0 	R-2.13.1
   R-2.2.0 	R-2.2.0-Xeon
   R-2.2.1 	R-2.2.1-Xeon
   R-2.3.0 	R-2.3.1
   R-2.3.1-Xeon 	R-2.4.0
   R-2.4.1 	R-2.5.0
   R-2.5.1 	R-2.6.0
   R-2.6.1 	R-2.6.2
   R-2.7.0 	R-2.7.1
   R-2.7.2 	R-2.8.0
   R-2.8.1 	R-2.9.0
   R-2.9.1 	R-2.9.2
   R-alpha 	R-beta
   R-core-style 	R-devel
   R-devel-32 	R-devel-32-Fedora_11
   R-devel-32-Fedora_13 	R-devel-32-debian
   R-devel-32-memprof 	R-devel-64
   R-devel-64-Fedora_11 	R-devel-64-Fedora_13
   R-devel-64-MM 	R-devel-64-RH5
   R-devel-64-debian 	R-devel-64-debian-1
   R-devel-64-memprof 	R-devel-MM
   R-devel-RH5 	R-devel-RHEL
   R-devel.~1~ 	R-devel.~2~
   R-devel.~3~ 	R-devel.~4~
   R-devel.~5~ 	R-devel.~o~
   R-devel~ 	R-fix-T-F
   R-fix-miscellaneous 	R-indent-all
   R-indent-cautiously 	R-mode
   R-newest 	R-patched
   R-patched-32 	R-patched-32-Fedora_11
   R-patched-32-Fedora_13 	R-patched-32-debian
   R-patched-64 	R-patched-64-Fedora_13
   R-patched-64-debian 	R-patched-MM
   R-patched-RHEL 	R-patched-shlib
   R-patched-shlib-64-Fedora_13 	R-patched-shlib~
   R-patched.~1~ 	R-patched.~2~
   R-patched.~3~ 	R-patched.~4~
   R-patched.~5~ 	R-patched.~6~
   R-patched.~7~ 	R-patched.~8~
   R-patched.~9~ 	R-patched_old
   R-pre-rel 	R-rc
   R-site-search 	R-transcript-mode
   R-valgrind 	Rd-describe-major-mode
   Rd-font 	Rd-mode
   Rd-mode-calculate-indent 	Rd-mode-indent-line
   Rd-mode-insert-item 	Rd-mode-insert-section
   Rd-mode-insert-skeleton 	Rd-mode-menu-map
   Rd-preview-help 	Rd-submit-bug-report
   Rnw-mode

so you see that I get pretty many installed versions of R ...
and (almost) all are found by ESS automagically at startup.

For that to work they must be in the PATH,
and that's a concept working nicely in Unix-like OSs, but
possibly not in Windoze ... which I now guess is what you've got 
??

Regards,
Martin Maechler, ETH Zurich