== Quote from downs ([email protected])'s article > I've just committed a module to tools (tools.cpp, http://dsource.org/projects/scrapple/Trunk/tools/tools/cpp.d ) that should enable linking and using any C++ library with D programs without creating a C wrapper for it. > The code has been tested with a simple multiple-inheritance sample: http://paste.dprogramming.com/dpv8hpjp > The D code to bind to this is http://paste.dprogramming.com/dphlv1ot . It requires a symlink to the tools folder in its directory. > Caveats: > - D1 > - Only works on g++4's "newapi" layout and mangling (but should be reasonably portable). > - Diamond pattern is untested and unsupported. > - Class protection is completely unsupported - public only. > - RTTI must be generated manually (normally the compiler would do this). See the D half of the sample. > - Dynamic casting from and to generated classes is not implemented. > - The C++ code that does this is long and full of special cases, so > - For the example, I ended up hardcoding a manual translation between A > and B. > - If you need dynamic casting, I recommend hardcoding the required paths based on classinfo pointer comparisons. > - The C++ DSL parser is not very tested. Occasional bugs may occur. > - When building with LDC, fixup_vtable() needs to be called for every newly created C++ class object. > - This is because LDC does not yet support initialization from global variable addresses. > Building the sample is a two-step process: > g++ test.cpp -c -g -o test.o > gdc -J. cpp_demo.d tools/cpp.d tools/base.d tools/smart_import.d tools/ctfe.d tools/compat.d tools/text.d tools/tests.d tools/log.d test.o \ > -o cpptest -lstdc++ -L /usr/lib/gcc/i686-pc-linux-gnu/4.3.2/ -g # adapt > library path as appropriate > Writing this also gave us what I believe to be a fair contender to Most Horrifying Statement of D Ever Written: > fndefs ~= `mixin("extern(C) `~t~` "~`~mname~`~"`~fnparams~`; ");`~'\n'~ > `mixin("`~fn~`("~refToParamList("Params!(typeof(&"~`~mname~`~"))", isRef!(typeof(mixin("&"~`~mname~`))))~") { > return "~`~mname~`~"("~refToValueList(isRef!(typeof(mixin("&"~`~mname~`))))~"); > } > "); `; > --downs
Awesome! One quick question. This may be a stupid question, as I don't understand at all yet how this works: Can you instantiate C++ templates with this thing, or does it work only w/ non-templated C++ code?
