Philippe Grosjean wrote:
Hello,
Here are a few questions that would be useful to get an answer via
dedicated functions in utils or tools packages:
- When did function foo appeared in R or in a given package?
- When did argument myarg appeared in function foo?
- When did function bar get deprecated or when did it disappeared?
- I wrote a script using functions foo and bar with R 1.9.1. My script
does not work any more with current version. What were all the changes
made to foo and/or to bar since then (this could obviously help me to
update my script for current R version)?
Currently, we have to read NEWS (or perhaps a non official changelog)
manually to get such answers.
The basic function to retrieve data that would answer to these questions
would be something like:
> changes(c("foo", "bar"))
That function could, for instance, read information in a
computer-readable file named CHANGELOG... because the problem is there!
Changes are currently recorded in NEWS, but ONLY in a human-readable
form! A quick suggestion for a format for CHANGELOG by example:
There is the tools::readNEWS function to read the NEWS file. It's not
just human readable. That's what the RSS feed uses.
Date Object Action Value Message
2009-04-17 package commit 1.1-0 Enhanced version of my package
2009-04-15 foo add foo(y) New function foo in my package
2009-04-14 bar debug bar(NULL) returned wrong result
2009-04-01 package commit 1.0-0 First version of package on CRAN
It doesn't contain dates, and dates don't really make sense. (Many
additions are introduced over a sequence of changes. Do you give the
first date, the last date? What if the change is very minor, e.g. a
typo in the docs?) NEWS does contain R version numbers, and those are
well defined.
The RSS feed does list the date on which it noticed each change to the
NEWS file, but I think that is more useful for keeping up to date with
changes, rather than defining when something happened.
It should be kept simple. May be an "Author" field in the records would
be nice too. Also a function to record a new entry in the CHANGELOG
could look like:
Maybe you want the Subversion log. It is machine readable; just use
Subversion to read it. (Something nice would be R-level access to the
Subversion API.) You can be very specific about which files you want to
read about, or just read the whole thing on developer.r-project.org.
Duncan Murdoch
> track("XXX", action = "debug", message = "my comment", file =
"/somewhere/CHANGELOG")
The file NEWS would not change and should be kept to present the same
information in a human-readable format.
Also, a function that lists all functions used in a script or a package
(Romain François is working in this direction with svTools package),
plus a function to plot one or several "changes" objects as returned by
changes() on a time axis or "version axis" would be welcome additions to
further track and plot evolution of R, or of R packages for a group of
functions of interest. Finally, a function to easily record the
dependences used and their versions in a script would complete the set
of tools.
These 4-5 functions are not difficult to write (although I suspect that
this simplistic proposal would become more complex if one consider to
interact with subversion, to separate development and release versions,
...). But to be really useful, they should be better designed and
proposed by the R core team, and included in the official specifications
for writing package. May I suggest to think about such a change for R
version 3.0?
Things get more complicated for verifying CHANGELOG in R CMD check. At
least, one could check actions like:
- object or function addition, deprecation or disappearance,
- argument changes in functions, slot changes in objects,
- function refactoring (change in the code from previous version)
but only if we provide also the previous version of a package to R CMD
check.
I would be happy to contribute, but the concept must certainly be
further discussed and enhanced (here?), and then, accepted by the R core
team before going any further.
All the best,
Philippe Grosjean
______________________________________________
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel
