A new package arrived on CRAN a few days ago. It offers a few headers files which wrap (parts) of the C API for R, but in a form that may be a little easier to use for C++ programmers. I have always liked how in Rcpp we offer good parts of the standalone R Math library in a namespace R::. While working recently with a particular C routine (for checking non-ASCII characters that will be part of the next version of the dang package which collecting various goodies in one place), I realized there may be value in collecting a few more such wrappers. So I started a few simple ones starting from simple examples.
Currently we have five headers defines.h, globals.h, internals.h, math.h, and shield.h. The first four each correpond to an R header file of the same or similar name, and the last one brings a simple yet effective alternative to PROTECT and UNPROTECT from Rcpp (in a slightly simplified way). None of the headers are “complete”, for internals.h in particular a lot more could be added (as I noticed today when experimenting with another source file that may be converted). All of the headers can be accessed with a simple #include <tidyCpp> (which, following another C++ convention, does not have a .h or .hpp suffix). And a the package ships these headers, packages desiring to use them only need LinkingTo: tidyCpp.
As usage examples, we (right now) have four files in the snippets/ directory of the package. Two of these, convolveExample.cpp and dimnamesExample.cpp both illustrate how one could change example code from Writing R Extensions. Then there are also a very simple defineExample.cpp and a shieldExample.cpp illustrating how much easier Shield() is compared to PROTECT and UNPROTECT.
Finally, there is a nice vignette discussing the package motivation with two detailed side-by-side ‘before’ and ‘after’ examples that are the aforementioned convolution and dimnames examples.
Over time, I expect to add more definitions and wrappers. Feedback would be welcome—it seems to hit a nerve already as it currently has more stars than commits even though (prior to this post) I had yet to tweet or blog about it. Please post comments and suggestions at the GitHub repo.
If you like this or other open-source work I do, you can now sponsor me at GitHub. For the first year, GitHub will match your contributions.
This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.