On 2011-07-19 12:39, Loopback wrote:
On 2011-07-19 05:46, Johann MacDonagh wrote:
What is the best method to accomplish this, and are there any
limitations with this method (do I have to allocate the class with
malloc instead etc.)?
Your C++ class "Base" is not compatible with your D "Foo" class. The
v-tables are not guaranteed to be identical. I'm not even sure if D's
thiscall is the same as C++'s thiscall. It's just not going to work.
Most languages don't support this. This is why we use C bindings.
Everyone supports C ;)
Now, you can do something like this:
struct Foo
{
int x;
float y;
}
extern(C) void* GetNewFoo()
{
// Note: Don't use new here otherwise the GC may clean it up
return cast(void*) core.memory.GC.malloc(Foo.sizeof);
}
extern(C) float Foo_DoSomething(Foo* foo)
{
return foo.x + foo.y;
}
extern(C) void FreeFoo(Foo* foo)
{
core.memory.GC.free(foo);
}
I haven't tried this, but something like this should work. Structs are
inherently compatible between languages. Of course, you won't be able to
do any kind of polymorphism.
Does this help?
Very interesting!
This might help depends; are you able to have structures with functions?
Are they still analogous if you implement them?
Also, how come the class-interface inheritance didn't work to
communicate with C++. Is the "Interface to C++" doc's outdated?
"Calling D Virtual Functions From C++"
http://www.digitalmars.com/d/2.0/cpp_interface.html
I noticed that function seems to work functions with structures.
Are there any restrictions worth knowing or is it just like any other
structure when D and C++ communicate?
Can I have private variables, public, properties etc?
And just not to forget, why the C++ and interface class didn't work?
