svn diff -x -b

Hello; I find it a bit unfortunate that svn diff doesn't understand -b
(ignore whitespace) by default. It seems further unfortunate that in
order to pass -b to diff, one must change from:
  svn diff foo bar
to:
  svn diff --diff-cmd diff -x -ub foo bar

Yes, it works, but it's annoying. :) Anyway, it'd be keen if the built-in
differ could grok a larger subset of GNU diff's options, such as -b
(ignore whitespace) and -p (show C function).

Thanks :)