[ESS] feature request : completion of available packages name

[Martin Maechler]

>>>>> Samuel BARRETO <samuel.barreto8 using gmail.com>
>>>>>     on Wed, 4 Jan 2017 08:53:10 +0000 writes:

    > Thanks to you all !
    > C-c C-e C-l is quite a time saver indeed !

with thanks to Chuck, indeed.
HOWEVER: I'm discouraging its use in favor of the completion
mechanism below:

Very early in ESS history, i.e., the early '90s, we agreed on

  "The source code is real. The objects are realizations of the source code."

etc, e.g., see at
  http://ess.r-project.org/Manual/ess.html#Philosophies-for-using-ESS_0028S_0029

and in the mean time, with reproducibility and literate
programing "every where", you should have been taught to work
with *.R (or *.Rnw, *.Rmd, ..) scripts rather than doodling away
in the R buffer aka R console. ... which is really what
C-c C-e C-l is about.

Rather you *do* want the correct  require() / library()
function calls in your *source* code, right, as I mentioned:
 "The source code is real ... "

    > And running `rc.settings(ipck = TRUE)` does provide the kind of completion
    > I was thinking of.

    > ESS rocks.

yes indeed, thank you!
In this respect not the least thanks to all the R-side
completion work by Deepayan Sarkar!! 

Martin

    > Le mer. 4 janv. 2017 à 08:09, Deepayan Sarkar <deepayan.sarkar using gmail.com> a
    > écrit :

    >> On Wed, Jan 4, 2017 at 1:52 AM, Martin Maechler
    >> <maechler using stat.math.ethz.ch> wrote:
    >> > On Tue, Jan 3, 2017 at 6:30 PM, Samuel BARRETO
    >> > <samuel.barreto8 using gmail.com> wrote:
    >> >> Hi,
    >> >>
    >> >> Do you think it would be difficult to add some kind of completion
    >> backend
    >> >> to complete the package names when typing `library(` ?
    >> >> I was thinking that the list of packages could be populated by calling
    >> >> something like :
    >> >>
    >> >> names(installed.packages()[,2])
    >> >>
    >> >> But I don't know enough elisp to implement it myself…
    >> >
    >> > Don't do it the way Rstudio does (it has very slow startup time, in
    >> > parts of its interface, because it not only wants to know the package
    >> > names of all my many thousand packages in my dozen of libraries in
    >> > .libPaths(), but it also want to prepare all the help pages ... or
    >> > something close to that).
    >> >
    >> > More seriously: We do something like that already in ESS for quite a
    >> > while now.... but I don't recall the details.
    >> > You also may want to give more details about the kind of completion..
    >> > notably as emacs / ESS have quite a few different completion
    >> > possibilities, as we have been told recently here.
    >> 
    >> Try executing
    >> 
    >> rc.settings(ipck = TRUE)
    >> 
    >> in your R session or .Rprofile and see if it works. It should as long
    >> as ESS uses R's completion mechanism.
    >> 
    >> It does require running installed.packages() to create the cache,
    >> which can be slow the first time for large/NFS libraries, which is why
    >> it's disabled by default.
    >> 
    >> -Deepayan
    >> 

    > [[alternative HTML version deleted]]