Re: Newcomers to

[Brian Drummond <brian3@shapes.demon.co.uk>]

On Wed, 08 Oct 2014 09:23:18 +0200, Gour wrote:

> On Tue, 7 Oct 2014 10:49:10 +0000 (UTC)
> Luke A. Guest <laguest@archeia.com> wrote:
> 
>> Yeah hint taken. It's on the back burner but I do intend to get back to
>> it after my new site is going.
> 
> Fine, I hope your site's progress is going well. ;)
> 
> Just curious, in general, how much does '-fdump-ada-spec' help when
> generating (thin) C++ bindings?

My own gut feel on a couple of projects : it probably does 80-90% of the 
work, depending on the C/C++ styles involved.

One hardware interface library in C (to the Aardvark I2C/SPI USB 
interface from totalphase.com ) used a lot of macros for defining 
constants. These were untranslated, appearing as comments in the Ada 
package (apparently because they were untyped numbers). 

I copied them into a separate package, "aardvark_constants" alongside  
the autogenrcated "aardvark_h", uncommented and declared the half dozen 
or so constants I needed, leaving the rest as comments against future use.

It would have been a mistake to do this in the autogenerated file because 
you couldn't autogenerate it anew...


On a C++ project several years ago I found it made a poor job of 
processing C++ templates - perhaps not surprisingly - and the result 
needed about 20% rewritten by hand. This may have improved since, but I 
wouldn't be surprised if there are still problems in there.


Incidentally '-fdump-ada-spec-slim' often does a better job rather than 
polluting your project with the full transitive closure of the C 
namespace... '-fdump-ada-spec' merely reveals how awful the #include 
mechanism really can get.

-- Brian