Re: Portability/Compatability between GNUstep <---> Cocoa...

[Kazunobu Kuriyama]

Richard Frith-Macdonald wrote:

> For both base and gui, MacOS-X extensions are intermingled with the 
> rest of the code, and there are compiler preprocesssor  values
> used to control #ifdef  statements in the headers so that application 
> programmers can decide whether their software builds with
> MacOS-X and GNUstep extensions available or not (the default is for 
> all extensions to be available to the application code). 

I'd like to know this point more.  As far as I know, there are two 
compilation switches STRICT_OPENSTEP
and NO_GNUSTEP for the purpose stated above.  The implications of 
'#define STRICT_OPENSTEP' and '#define
NO_GNUSTEP' are trivial, but that of '#if !defined STRICT_OPENSTEP' or 
'#if !defined NO_GNUSTEP' looks
fairly ambiguous.

(Also, I'm skeptical about allowing application programmers to use of 
marcos designed for internal use
of library development.  But this is another issue. )

Recently, I've made some non-trivial programs based on some Cocoa 
programming books and found some
concrete incompatiblilities between GNUstep and Cocoa. When I come 
across such an incompatibility,
I'm always at a loss because GNUstep doesn't provide any preprocessor 
macro which can be used just for
differentiating GNUstep code and Cocoa one.  I feel both STRICT_OPENSTEP 
and NO_GNUSTEP or their
negations are not appropriate for that purpose.

Is there already any macro, or an established idiom (i.e. GNUstep 
conventions) for the purpose?

If not, I think it would be better for us to have a certain macro 
predefined in GSConfig.h,
say __GNUSTEP_LIBRARY__, to distinguish GNUstep's headers from those of 
Cocoa.

> I'd like to put "bad" MacOS-X extensions in another subdirectory and 
> mark their use as not being recommended for style/simplicity
> reasons.  However, nobody has contributed any code in this category yet. 

I agree to this idea.  But is there anyone who contributes something if 
it is considered "bad"? :)

- Kazunobu Kuriyama