Message-ID: <23095.50515.694572.127889@bud.eddelbuettel.com>
Date: 2017-12-18T13:40:35Z
From: Dirk Eddelbuettel
Subject: Rcpp - Linking to DLL from another package?
In-Reply-To: <9DD73F68AC266D4AA329E07B678177B1F059D92A@EE-MBX3.ee.emp-eaw.ch>
(Moderately wrong list: r-package-devel for packaging questions, rcpp-devel
for Rcpp questions)
On 18 December 2017 at 13:24, Stravs, Michael wrote:
| I am trying to make a package B that extends another package A. Package A uses Rcpp, and I want to extend a class X used there.
It doesn't really matter (for the issue at hand) if you use Rcpp or not -- R
only offers us C interfaces so C interfaces are all we got. And they don't
know classes.
I worked through that in some of my packages. See eg RcppXts which "extends"
in your sense xts by allowing C++ level access from another package. The one
key aspect is that _everything you want to call from B must be explicitly
exported by A_. See Writing R Extensions for details.
If you could rewrite your class A to be header-only then you could just
include it via LinkingTo. But that is a different story.
In short, "No Free Lunch" and no automagic mechanisms.
Dirk
--
http://dirk.eddelbuettel.com | @eddelbuettel | edd at debian.org