Tiburón Sneak Peek: COM

I have a few minutes here so I want to write a bit about the major overhaul that went on with the Delphi and C++Builder COM feature. On the surface it might not look like much, but we really did overhaul the entire feature laying some much needed ground work for the future.



Here's a screen capture of the project manager after creating an ActiveX Library:







Notice the file with the .ridl extension in the project manager. This is a new file we have introduced in the next version of Delphi and C++Builder called Restricted Interface Definition Language (RIDL). The .ridl file is now the storage file for your type library instead of a binary .tlb file. A new tool has been built called gentlb.exe (similar to midl.exe) that compiles .ridl files into .tlb files. It is part of the toolchain so you can build from the IDE or the command line. Of course from the IDE you get the code updaters for when you add new methods and the stubs are generated for you. But you can also do all that by hand if you desire. We now treat the .tlb file as any other intermediate file like a .obj or .dcu, so eventually it'll be safe to add it to your clean list. Make sure you back up the original .tlb first. From now on you can diff and merge changes to the .ridl file as you would any other text file. This should really enable more than one developer to work on a COM project.



Here is a screen capture of the new type library editor:







Notice there are tabs at the bottom similar to what you see with the form designer. From left to right Code, Design and History.

Yeah, we have a history view just like any other text file in the IDE:







And of course you can look at the .ridl file like any other text file. Here is a screen capture of the Code tab of the type library editor:







If you know IDL you'll find that RIDL isn't really any different. In fact it has been our goal to make sure that midl.exe can compile .ridl files. So we didn't make up our own language here, it's industry standard.