Re: Help needed to simplify code for customisation

[Kevin Rodgers]

Richard Riley wrote:
> Could someone please recommend the best way to remove the 3 similar lines
> doing string-match on the "account" assign and iterate a variable list to
> which I can "add-to-list" in other .el libraries for example?
>
> ,----
> |  (if (message-mail-p)
> |       (save-excursion
> |       (let* ((from
> |               (save-restriction
> |                 (message-narrow-to-headers)
> |                 (message-fetch-field "from")))
> |              (account
> |               (cond
> |                ((string-match ".*root.*" from)"richardriley")
> |                ((string-match ".*richardriley.*" from)"richardriley")
> |                ((string-match ".*rileyrgdev.*" from)"rileyrgdev")
> |                ))
> |              )
> |         (setq message-sendmail-extra-arguments (list "-a" account))
> |         )))
> |   )
> `----
>
> Thanks for any pointers,

Why not use message-field-value instead of message-fetch-field, since
it takes care of the narrowing as well?

(string-match ".*foo.*" BAR) is equivalent to (string-match "foo" BAR)
when used as a predicate.

Your patterns are not very specific and admit false positives e.g.
"FOO@BARrichardrileyBAZ.com" and "foo@bar.com (not richardriley)".
At the very least, they should be anchored with \< and \>.

Better yet, use mail-header-parse-address to split the header into
MAILBOX and COMMENT components, then match only on MAILBOX.

Here's what I came up with:

(defvar my-sendmail-accounts
  '(("root" . "richardriley") ("richardriley") ("rileyrgdev"))
  "Alist of (MAILBOX . ACCOUNT) pairs.  If ACCOUNT is nil, use MAILBOX.")

(when (message-mail-p)
  (let ((sender (car (mail-header-parse-address (message-field-value 
"From"))))
        (accounts-regexp (format "\\`\\(%s\\)\\>"
                                 (mapconcat (function car)
                                            my-sendmail-accounts
                                            "\\|")
                                 )))
    (when (string-match accounts-regexp sender)
      (let ((mailbox-account (assoc (match-string 0 sender)
                                    my-sendmail-accounts)))
        (setq message-sendmail-extra-arguments
              (list "-a" (or (cdr mailbox-account)
                             (car mailbox-account))))))))

--
Kevin Rodgers
Denver, Colorado, USA