Re: Using ObjectAda 7.1 SE lib in VC++ 5.0

[Stephen Leake <Stephen.Leake@gsfc.nasa.gov>]

"Kai Glsner" <kai.glaesner@daimlerchrysler.com> writes:

> Hello community,
> 
> currently I'm using ObjectAda 7.1 SE to become familiar with Ada-95. Is it
> possible to use any code (e.g. the object-file or a library), written with
> this environment, as a static library in VC++ 5.0? And if "yes", how to do
> this.

Yes, you can.

You need to add 'pragma Export (C, ...)' for each Ada function you
want to call from C++. In C, you need to declare the Ada functions
with 'extern C'.

ObjectAda will build object files (.obj). You can either just link
those directly into your VC++ project, or use the MS tools to build a
library.

> The background is, that I would like to migrate to Ada-95 in a soft but
> steady manner, starting with doing some libs in Ada, and then, may be, do
> most of it with Ada-95, that means, calling C-Sources from Ada......

Wait a minute - above you implied you wanted to call Ada from C++. Now
you want to call C from Ada. This is equally possible, using pragma
Import. However, calling C++ member functions is generally not
possible; you'll need to provide an 'extern C' wrapper.

Either way, a gradual transition is definitely the way to go.

-- Stephe