Newbe hacker, interface question on includes...

I have begun perusing the source, eventually hoping to
contribute to the development effort. I have noticed that
long ago the include files for a "component" were in the
component directory, eg src/backend/catalog/Attic/catalog.h,v
(here I'm assuming that Attic means a storage place for
items that use to be there but are no longer there...)
and now this file resides in src/include/catalog/catalog.h,v. A quick
scan seems that this was a common transformation.

This seems to be a mighty step backwards, especially if
one considers the recommendations on large systems development
where you want to minimize dependancies...

Could someone point out the history of code relocation and rationale.

Thanks for any pointers.

Best regards,

.. Otto

Otto Hirr
OLAB Inc.
otto(dot)hirr(at)olabinc(dot)com
503 / 617-6595