how to hg diff patch or diff files?

[TK Soh]

On 7/18/07, Bryan O'Sullivan <bos at serpentine.com> wrote:
> Christian Ebert wrote:
>
> > Is there an easier (encode/decode filter?) way to hg diff patch
> > or diff files than:
> >
> > $ hg cat file.patch | interdiff /dev/stdin file.patch
>
> Yes, documented in http://hgbook.red-bean.com/hgbookch13.html near the end.
>
> The following file is the one you want to act as an adapter between the
> extdiff extension and interdiff.
>
> http://hg.serpentine.com/mercurial/book/raw-file/tip/examples/hg-interdiff

maybe this can be turned into an 'hg interdiff' extension?