[R-pkg-devel] Properly referencing copied code

? Thu, 11 Jul 2024 20:58:53 +0000
DRC via R-package-devel <r-package-devel at r-project.org> ?????:

1. How does linking to external libs differ from providing the source
of a library and linking against that?

I think that the author information in the DESCRIPTION is about what
your package provides by itself, not everything that may end up in the
address space once the package is loaded. Since CRAN prefers
self-contained packages, we end up including them in our packages
(unless the third-party library is already very common and present in
RTools & macOS recipes & common GNU/Linux distros), which requires us
to specify their authors.

Do I need to provide references to lapack and blas if they aren't
shipped with the package? What about math (lm)?

No.

2. What roles to supply to authors of external software?

Do I need to differentiate between authors with explicit copyrights
`c('ctb', 'cph')` vs those who are authors but are not listed as
copyright holders `c('ctb')` in the third party source? Or just give
everyone both?

I would expect most authors and contributors to be copyright holders
too, but it must be possible to contribute without providing patches
and becoming one. E.g. a project might recognise a tester and bug
reporter as a full author, but there is no code that they own any
copyright on.

3. One of my dependencies has a lot of copyright holders throughout
the source. Most of these are for individual functions and cmake
files that are not directly used by my package. What is the best way
to handle this? Add as much of the unused parts of the third party
package to the .Rbuildignore file as possible to filter out the
unused parts?

If it's feasible to implement, omitting unused files from the tarball
is a good idea.

4. Is there a better place to put all these authors? The author list
has already gotten large and I still have many more to add.

CRAN recognises inst/AUTHORS. Here's a recently released package with
no obvious problems that makes use of it:
https://CRAN.R-project.org/package=xlcharts

We should probably document it somewhere.

Best regards,
Ivan