Re: trailing whitespace visible on some buffers

[Edward O'Connor]

> This is an elementary question, but I haven't found the solution
> of my problem.
> 
> I want to set the buffer-local variable
> `show-trailing-whitespace' to `t' for all buffers

(setq-default show-trailing-whitespace t)

> except for *info*, *diary*, *calendar*, and *mail presentation*.

(let ((hook (lambda () (setq show-trailing-whitespace nil))))
  (mapc (lambda (var)
          (add-hook var hook))
        '(info-mode-hook calendar-mode-hook diary-hook)))

Untested.

Sorry, I don't know what the *mail presentation* buffer is.


HTH

-- 
Edward O'Connor
ted@oconnor.cx