Re: RFA: [guile] Header inclusion update [Error building project using gnustep-guile]

[David Ayers]

Adam Fedor wrote:

> David Ayers wrote:
>
> > Hi,
> > ScriptKit
> >        * Library/Guile.h: Use qualified <gnustep/guile/header.h> path 
> > for
> >        inclusions.  Use "" rather than <> for local inclusions.
> >        * Library/GuileInterpreter.h: Use "" rather than <> for local
> >        inclusions.
> >        * Library/GuileScript.h: Ditto.
> >        * Library/SKInterpreter.h: Ditto.
> >        * Library/SKScript.h: Ditto.
> >        * Library/GuileSCM.h: Use qualified <gnustep/guile/header.h> path
> >        for inclusions.
>
> Just look at this. Aren't these headers installed eventually? So they 
> would need to keep the <> inclusion for that.

Yes the are installed, but that doesn't mean that they have to use 
<ProjectIncludeDir/header.h>.  They can use "header.h".
This is because...
http://gcc.gnu.org/onlinedocs/gcc-3.2.2/cpp/Include-Syntax.html#Include%20Syntax

|#include "|file|"|
   This variant is used for header files of your own program. **It
   searches for a file named file first in the directory containing the
   current file**, then in the same directories used for |<|file|>|.

So, if I want to *use* a ScriptKit header, my project would:
#include <ScriptKit/gg_Object.h>
this contains:
#include "gstep_guile.h"
which would be searched for in the same directory in which gg_Object.h 
was found.

This might even speed up the preprocessing a bit, as it doesn't need to 
go through the -I paths.  I think this should be the general technique.  
I'm sure Apple used to do the same for Foundation.h (except they used 
import instread of include.  I'd be surprised if they don't anymore.  I 
believe why most people do not use this technique is because they are 
either not aware of it, or they fear ambiguity about which header is 
included, when the don't qualify the path.  This can only happen if the 
file didn't exist.  But that just a bug in my view.  If you prefer, I 
have no problem reverting it before I commit.

Cheers,
Dave