[Rd] index.search

[Duncan Murdoch]

On 16/06/2014 3:32 AM, Martin Maechler wrote:
> >>>>> Adrian Dușa <dusa.adrian at unibuc.ro>
> >>>>>     on Mon, 16 Jun 2014 08:33:59 +0300 writes:
>
>      > On Mon, Jun 16, 2014 at 6:37 AM, Gabriel Becker
>      > <gmbecker at ucdavis.edu> wrote:
>      >> [...]  You can. This is valid R source, so the parser
>      >> will understand it
>      >>
>      >> expr = parse(text= example("deMorgan", package="QCA",
>      >> give.lines=TRUE))
>      >>
>      >> You can then evaluate some or all of that expression
>      >> using either R's own eval package or, e.g. Hadley
>      >> Wickham's evaluate package (for your particular usecase
>      >> evaluate will be easier I think).
>
>      > Oh, I see...! In that case I can use it, of course.  Did
>      > install the evaluate package, although one would expect
>      > some better documentation (no examples at all, especially
>      > at the main evaluate function).
>
>
>      >>> [...]
>      >> index.search is an unexported function, which means that
>      >> it is subject to change in how it behaves without notice
>      >> or even externally available reasons. You can get it via
>      >> :::, but again, it's really not the right tool here, and
>      >> not safe to use in general in code you expect to keep
>      >> working.
>
>      > Yes, I figured that much.  Of course it's not meant to be
>      > used in any decently working code, but I learn heavily by
>      > simply looking at these sort of (hidden) R functions.
>
>      > Thanks again, Adrian
>
> Apropos "not the right tool".  I'm a bit astonished that nobody
> mentioned the fact R already provides "the tool" to
> automatically compare all example outputs with a previous
> version (of the packages example outputs):
>
> *THE* manual (every package writer should know about,
>   re-read/browse about once a year, and search in for such questions):
>
> "Writing R Extensions", section Package subdirectories
> ----------------------------
> (e.g. on the CRAN master in Vienna,
>   http://cran.r-project.org/doc/manuals/R-exts.html#Package-subdirectories )
> says
>
> |    If directory 'tests' has a subdirectory 'Examples' containing a file
> |    'PKG-Ex.Rout.save', this is compared to the output file for running the
> |    examples when the latter are checked.
>
> So: After an 'R CMD check <PKG>' you only need to take and
> keep the  <PKG>-Ex.Rout  file that is produced (in the
> PKG.Rcheck/ directory), and save it into <PKG>/tests/<PKG>-Ex.Rout.save
> and from then on, every time you run R CMD check <PKG>  the
> comparison will be made.

It's also worth mentioning that there is something similar to test for 
changes to vignettes:

> If there is a target output file .Rout.save in the vignette source 
> directory, the output from running the code in that vignette is 
> compared with the target output file and any differences are reported 
> (but not recorded in the log file). 

The slightly surprising thing is that R CMD check doesn't produce 
<vignette>.Rout; the file that is compared to <vignette>.Rout.save is 
<vignette>.log.

Duncan Murdoch