font-lock-keywords uses only facename

[Alex Schroeder <alex@emacswiki.org>]

Today I wrote a very small generic mode for lists of emails.
define-generic-mode's parameter font-lock-list is used to set
font-lock-keywords, eventually.

My problem was that I didn't know that font-lock-keywords doesn't
take faces.  It only takes expressions that evaluate to faces.
Therefore, the following font-lock-list doesn't work.  Only the
keyword regexp is shown:

(defface mail-list-whitespace '((t (:background "orange"))) "For whitespace.")
(defface mail-list-empty-lines '((t (:background "red"))) "For empty lines.")

(define-generic-mode 'mail-list-mode
  nil
  nil
  '(("^[a-z]+@[a-z.]+\\.[a-z][a-z]+$" . font-lock-keyword-face)
    ("[ \t]+" . mail-list-whitespace)
    ("^\n" . mail-list-empty-lines))
  '("\\blist\\'")
  nil
  "Mode used for Minimalist lists: One email per line.")

I must either use variables:

(setq mail-list-whitespace 'mail-list-whitespace)
(setq mail-list-empty-lines 'mail-list-empty-lines)

Or I must use quotes inside the list:

(define-generic-mode 'mail-list-mode
  nil
  nil
  '(("^[a-z]+@[a-z.]+\\.[a-z][a-z]+$" . font-lock-keyword-face)
    ("[ \t]+" . 'mail-list-whitespace)
    ("^\n" . 'mail-list-empty-lines))
  '("\\blist\\'")
  nil
  "Mode used for Minimalist lists: One email per line.")

Is this on purpose?  Would it break anything if using faces were
allowed directly?

Alex.
-- 
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..O  Schroeder's fourth law:
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