How to actually link to cctz from external package? about rcppcctz

[eddelbuettel]

As a start, I could export the parse and format functions for you at the C level. Would that help?

[vspinu]

Not really. I need full CCTZ API. Would really help if you could somehow put an object archive into the include folder so that I can pull it with -lcctz from Makevars.

[eddelbuettel]

That is beyond the scope of this package and project. Look at the line count of CCTZ and all the classes.

I'd rather talk to upstream about to ensure the build is header only, if only for subsets. Boost is similar. You can use Boost date_time header-only for as long as you forgo string operations (either parsing or formatting or both).

Here, I went to CCTZ to get the parsing and formatting explicitly so I don't mind the fact that the package itself is linking.

But in general you can't "just" assume a C++ library from another R package. Once you are at the linking stage you are in the hands of the OS. Now, carefully done header libraries can help here. Maybe there is scope. Talk to upstream -- it is not an RcppCCTZ issue.

[vspinu]

That is beyond the scope of this package and project. Look at the line count of CCTZ and all the classes.

I actually meant to create an archive of compiled objects and keep it in RcppCCTZ path somewhere accessible. Something along these lines:

LIBCCTZ=cctz/time_tool.o \
   cctz/time_zone_fixed.o \
    cctz/time_zone_format.o \
    cctz/time_zone_if.o \
    cctz/time_zone_impl.o \
    cctz/time_zone_info.o \
    cctz/time_zone_libc.o \
    cctz/time_zone_lookup.o \
    cctz/time_zone_posix.o

$(SHLIB): libcctz.a

libcctz.a: $(LIBCCTZ)
	$(AR) rcs libcctz.a $(LIBCCTZ)

Then move libcctz.a into an accessible place. Isn't this doable?

[eddelbuettel]

I would tend to say "No", and quite firmly.

I don't think I have seen this suggested, let alone, recommended on r-devel or in Writing R Extension.

[eddelbuettel]

I understood your question as asking whether the RcppCCTZ could provide the static library, and I still don't think so.

Compiling locally at your use for use in the same is possible. That is closer to you embedding the sources yourself. May still be brittle.