How to use SWIG for D from C++ on Windows?

Question

I want to use LEAP Motion in D.
Therefore It doesn't have C library and It has only C++ library.
I tried SWIG 2.0.9 below command.

swig -c++ -d -d2 leap.i 

This command output Leap.d, Leap_im.d, Leap_wrap.cxx, Leap_wrap.h.
However, I don't know how to use to wrapper in D and I can't find how to use the wrapper.
Link error displays to use it intact.
How use these wrapper in D2?
And can I use without Leap.cpp (source of Leap.dll)?

Update:

Thanks two answers. and sorry for reply late because of busy.
Say first conclusion I could build Leap sample code on Win64 by following the steps below.

1. Output wrappers by above command.
2. Create x64 DLL with VC2010 from Leap_wrap.cxx, Leap_wrap.h, and import Leap.lib(x64).
3. Compile Leap.d and Leap_im.d with dmd -c.
4. Build LeapTest.d with Leap.obj and Leap_im.obj

all command is below.

swig -c++ -d -d2 leap.i
dmd -c Leap.d Leap_im.d -m64
dmd LeapTest.d Leap.obj Leap_im.obj -m64
execute LeapTest.exe (require x64 Leap.dll and Leap_wrap.dll)

I could run Leap Program.
But program crach onFrame event callback.
I'll try again on x86 and investigate the causes.

Answer 1

Few helpful links (some information may be outdated):

• http://klickverbot.at/blog/2010/11/announcing-d-support-in-swig/
• http://www.swig.org/Doc2.0/D.html
• http://www.swig.org/tutorial.html

I have never used SWIG personally but my guess based on general knowledge about SWIG:

• Leap_wrap.cxx is C++ source file that wraps calls to C++ functions from target library in extern(C) calls
• Leap_wrap.h is header file with all extern(C) wrappers listed
• Leap_im.d is D module based on Leap_wrap.h with same extern(C) function listed
• Leap.d is D module that uses Leap_im.d as an implementation and reproduces API similar to original C++ one.

So in your D code you want to import Leap.d module. Than compile Leap_wrap.cxx to an object file with your C++ compiler and provide D object files, Leap_wrap.o and target library at linking stage. That should do the trick.

P.S. Leap.cpp source should not be needed. All stuff links directly from Leap_wrap.cxx to target library binary.

Answer 2

Go to IRC, either FreeNode, or OFTC, channel #D. In order to help you, we have to see what is in those files. My first guess is that you have to compile both D files, and the C++ file into object files, and link them together. I suppose SWIG is going to flatten the C++ API into bunch of C functions, and that is probably what Leap_wrap.cxx does.

If the LEAP API is not complex (ie. just bunch of simple C++ classes), it may be possible to directly interface with it. Read more about it here: http://dlang.org/cpp_interface.html .