[Proj] [patch] add missing projects.h

[Frank Warmerdam]

On Mon, Apr 9, 2012 at 8:03 AM, Judd Taylor <judd.t at orbitalsystems.com> wrote:
> I'd like to add some information about the problem we're seeing with the missing projects.h file.
>
> The code in question is a PDL (perl data language) binding to the Proj library written back in 2002 or 2003. This code uses projects.h to get the enumeration of the projections and their parameter for use in a code generator that writes the actual bindings and docs used for the interface.
>
> As far as I know, this is not available through proj_api.h. I've not worked directly with Proj since the way back on version 4.4.7, when the above solution using projects.h was suggested on this list. Can anyone here confirm whether this functionality is present in the proj_api.h that ships with 4.8.0?
>
> I'm specifically looking for the function pj_get_list_ref(), which is defined in projects.h.


Judd,

Since PDL uses pj_get_list_ref() and directly uses PJ_LIST objects you
are not using the public API, you are using the internal private API.

As such you need to include projects.h, but you shouldn't
expect to build against normal "install" copies of PROJ.4.

I would be open to ways of publishing the various lists but I think
some consideration will be needed.  What I don't want to do is
to expose the internal structures and make the ABI extremely
fragile.  I must confess I'm also not sure why PDL needs the
lists.  It doesn't seem necessary for a minimal bindings.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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