How to use D for cross platform development?

[Bennie Copeland]

On Thursday, 29 March 2012 at 16:36:57 UTC, Jacob Carlborg wrote:
> On 2012-03-29 14:44, Chris W. wrote:
>
>> Thanks for the link. Objective-C is basically C and can be 
>> implemented
>> in C style as far as I know. Is it worth going down to the C 
>> level like so:
>
> Yes that would be possible.
>
>> struct NSObject {
>> struct objc_class* isa;
>> }
>> struct objc_class {
>> Class isa;
>> Class super_class;
>> const char *name;
>> long version;
>> long info;
>> long instance_size;
>> struct objc_ivar_list *ivars;
>> struct objc_method_list **methodLists;
>> struct objc_cache *cache;
>> struct objc_protocol_list *protocols;
>> }
>>
>> Just a random thought.
>
> That's the alternative approach, I've done that as well. It's 
> very tedious and becomes verbose very fast.
>
> Both I and Michel have created an Objective-C/D bridge that 
> uses this approach. It lets you call Objective-C methods, 
> create instances of Objective-C classes, create subclasses in D 
> that inherit from Objective-C classes and so on. It did this 
> all automatically. The problem with the bridge was the enormous 
> template bloat. A GUI Hello World application takes around 60MB 
> with the bridge.
>
> http://www.dsource.org/projects/dstep
> http://michelf.com/projects/d-objc-bridge/
>
> That's why Michel started the DMD fork to directly support 
> binding to Objective-C classes and methods.
>
> If you just have a small amount of Objective-C code that needs 
> to be called and basically never changes then it won't be a 
> problem using the Objective-C runtime functions. Otherwise I 
> wouldn't recommend it.
>
> I've ported the SDL initialization code for Mac OS X to D, to 
> be used in derelict. This doesn't contain any fancy templates 
> like the bridge uses to help making the code less verbose. It's 
> quite a lot of D code compared to the Objective-C code:
>
> http://dsource.org/projects/derelict/browser/branches/Derelict2/DerelictSDL/derelict/sdl/macinit
>
> This would be the original Objective-C code:
>
> http://codespeak.net/svn/pypy/dist/pypy/rlib/rsdl/macosx-sdl-main/SDLMain.m
>
> If you're going with this approach you could have a look at my 
> bridge if you need help, it has some useful documentation of 
> how it works and is implemented:
>
> http://www.dsource.org/projects/dstep/wiki/ObjcBridge/BridgeInternals

Thanks for your help. My primary use case is to provide a native 
look and feel GUI on the Mac. So, to the extent of creating the 
interface using Cocoa and tying it back to the core code written 
in D.