"man gitattributes" doesn't explain comma-separated attribute values

  more nitpicking, but i'm working my way through the intricacies of
attributes and putting together some (allegedly) simple examples for a
class i'm giving on monday, and i noted a couple possible shortcomings
in "man gitattributes".

  as a working example, i looked at the top-level .gitattributes file
in the git source code itself, which opens with:

  * whitespace=!indent,trail,space
  *.[ch] whitespace=indent,trail,space diff=cpp
  *.sh whitespace=indent,trail,space eol=lf
  ... snip ...

first observation is that i see nothing in the man page that explains the notion of a comma-separated list of attribute values. maybe i missed it or maybe it's supposed to be intuitively obvious, but there's nothing i can see that mentions the possibility.

  related to that is that there is no explanation as to how to
interpret:

  * whitespace=!indent,trail,space

does the "!" apply to "indent" or to the entire list? the man page doesn't say.

  just being pedantic again.

rday