seperate commits for objects already updated in index?

Hi,

Dumb question, imagine you made changes to a few files, and ran update-index at various stages in between:

$ git status # # Updated but not checked in: # (will commit) # # modified: foo/ChangeLog # modified: foo/whatever # modified: bar/ChangeLog # modified: bar/other

The changes in bar/ are unrelated to the changes in foo/ - how do you commit each seperately? Git doesn't seem to want to let me:

   $ git commit -o bar
   Different in index and the last commit:
   M       bar/ChangeLog
   M       bar/other
   You might have meant to say 'git commit -i paths...', perhaps?

git commit on its own wants to commit all the above files.

what's the silly thing I've missed?

Thanks.

regards,