Re: auto-mode-alist, adding two modes

[Gijs Hillenius <gijs-nopsam-@hillenius.net>]

On  8 Oct 2007, Joost Kremers wrote:

> Gijs Hillenius wrote:
>> I would like to get emacs to use longlines-mode *and* flyspell-mode
>> for all files ending in .txt
>>
>> If I add this in my .emacs 
>>
>> (add-to-list 'auto-mode-alist '("\\.txt\\'" . longlines-mode ))
>>
>> followed by a similar line for flyspell, ignores the first, and uses
>> only the latter.

> you should read the documentation of auto-mode-alist. it says quite
> clearly that it is a list for specifying *major* modes. both
>
> longline-mode and flyspell-mode are minor modes, and should
> therefore be specified in a different way.
>
> not explicitly stated, but still deducible from the documentation is
> the fact that only the *first* matching regexp in auto-mode-alist is
> used. so once flyspell-mode has been found, the list is not searched
> further anymore.[1] this makes sense, because a buffer can only have
> one major mode.
>
> note that auto-mode-alist already specifies a major mode with files
> ending in .txt, namely text-mode. your customisation therefore
> disables text-mode for .txt files, which is probably not what you
> want. 
>
> to do what you want, you may add flyspell-mode and
> longlines-mode to text-mode-hook: 
>
> (add-hook 'text-mode-hook 'longlines-mode)
> (add-hook 'text-mode-hook 'flyspell-mode)
>
> adding these two minor modes to text-mode-hook makes sure that they are
> always turned on when text-mode is selected.
> 
> see (info "(emacs)Hooks") for details on hooks.[2]

Thanks for these speedy replies.

I do *not* want to add both of these minor modes to text-mode, for
this messes up other applications, such as my dear gnus.

So, I settled on 

(add-to-list 'auto-mode-alist '("\\.txt\\'" . longlines-mode ))
(add-hook 'longlines-mode-hook 'flyspell-mode)

The latter of which, if I understand it correctly, adds a fly-spell
wherever I have longlines-mode. Which is something I can live with,
for now.

Gijs