On 07/06/2011 9:08 AM, oliver wrote:
Hello,following an advice here from the list I looked into sources of other packages (xts) and found the TYPEOF() macro/function, which really is helpful. I iused the follwong code snippet: switch( TYPEOF( filename_sexp ) ) { case STRSXP: filename = CHAR( STRING_ELT(filename_sexp, 0) ); break; default: error("filename argument must be a string"); break; } Here, filename is of type char* and one function opens a file with that name. So it is purely intended to just grab out the char* from the String-Expression. Am I doing something wrong here, or is it ok, but I have somehow to say the extracting macros/functions, that it is really intended to throw away information and that a warning is not necessary?
The result of calling CHAR should be a "const char *". You are not allowed to touch the string it points to.
Duncan Murdoch ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
