If a pkg is made of several parts which all build from
the same distfile AND I want to keep the patches in
one place AND I want to speed up things by using
EXTRACT_ELEMENTS, I'm forced to override the "patch"
target because the patching generates fatal errors
if a file is not present.
This is annoying of course.

Examples are x11/py-Tk, devel/py-idle and devel/py-readline
which all are built from the original Python distribution file.

Can we simply add some "--batch" argument to "patch" (to
avoid prompting) and ignore errors if PATCHDIR and EXTRACT_ELEMENTS
both are defined, or do we need something more elaborate?
(eg checking the patch whether the file matches something in
EXTRACT_ELEMENTS)

best regards
Matthias