thread sorting docs

thread sorting docs

[Dan Christensen]

The info node "Sorting the Summary Buffer" says

>    By default, sorting is done on article numbers.  Ready-made sorting
> predicate functions include `gnus-thread-sort-by-number',
> `gnus-thread-sort-by-author', `gnus-thread-sort-by-subject',
> `gnus-thread-sort-by-date', `gnus-thread-sort-by-score',
> `gnus-thread-sort-by-most-recent-number',
> `gnus-thread-sort-by-most-recent-date', `gnus-thread-sort-by-random'
> and
> `gnus-thread-sort-by-total-score'.
> 
>    Each function takes two threads and returns non-`nil' if the first
> thread should be sorted before the other.  Note that sorting really is
> normally done by looking only at the roots of each thread.

Should the last sentence be changed to 

  Note that sorting is done by looking only at the roots of each
  thread, except for the functions
  `gnus-thread-sort-by-most-recent-number' and
  `gnus-thread-sort-by-most-recent-date' which look at the 
  most recent message in each thread.

Later in the same node:

>    If you want to sort by score and then reverse arrival order, you
> could say something like:
> 
>      (setq gnus-thread-sort-functions
>            '((lambda (t1 t2)
>                (not (gnus-thread-sort-by-number t1 t2)))
>              gnus-thread-sort-by-score))

Is the lambda necessary?  Why not just

>      (setq gnus-thread-sort-functions
>            '((not gnus-thread-sort-by-number)
>              gnus-thread-sort-by-score))

Dan