I would like to propose that Rf_mkString(NULL) and Rf_mkChar(NULL) return NA rather than segfault.
Case: the mkString() and mkChar() functions are convenient to wrap strings returned by e.g. external C libraries into an R vector. However sometimes a library returns NULL instead of a string when the result is unavailable. In some C libraries this can happen unexpectedly or is even undocumented. A good R package author always checks results for a null pointer, and deals with it accordingly. But sometimes we make assumptions. There was an example in the 'curl' package where a documented version string was suddenly NULL if libcurl was built with some unusual configuration. These problems are hard to catch and I don't see any benefit of segfaulting for such edge cases. Some packages use a macro like this to protect against such problems: #define make_string(x) x ? Rf_mkString(x) : ScalarString(NA_STRING) But I think it would make sense if this was the default behavior in Rf_mkString and Rf_mkChar. ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
