Tool for writing thin wrappers for changing existing elisp configurations

Tool for writing thin wrappers for changing existing elisp configurations

[Andrey Tykhonov]

Hi List,

is there any way to change configuration files by means of elisp functions?
Which of them may help?

For example, there are such lines in the ~/.gnus.el (but please note that
that question is not about Gnus):

#+begin_src elisp
(setq nnmail-split-fancy
      '(|
        (: nnmail-split-fancy-with-parent )
        (any "help-gnu-emacs@gnu\\.org" "help-gnu-emacs")
        (any "emacs-devel@gnu\\.org" "emacs-devel")
        "mail.misc"))
#+end_src

I would like to write a thin wrapper, interactive elisp function, which
will be able to append new entry to the `nnmail-split-fancy'.

When I will call that function (M-x add-nnmail-split-fancy-entry) then I'll
be prompted for email address and imap folder (let 'any' will be
hard-coded). Thus such command execution:

M-x add-nnmail-split-fancy-entry RET emacs-orgmode@gnu.org RET
emacs-orgmode RET

will change configuration of the mentioned lines to the following:

#+begin_src elisp
(setq nnmail-split-fancy
      '(|
        (: nnmail-split-fancy-with-parent )
        (any "help-gnu-emacs@gnu\\.org" "help-gnu-emacs")
        (any "emacs-devel@gnu\\.org" "emacs-devel")
        (any "emacs-orgmode@gnu\\.org" "emacs-orgmode")
        "mail.misc"))
#+end_src
        
Yes, of course, I can just open ~/.gnus.el and add such entry. And of
course I can change via M-x customize-variable RET nnmail-split-fancy RET.

But this question is not about *how* to change existing elisp configuration
but about a tool. I wonder: is there any elisp tool (package, functions
etc) which allows to write such a thin wrapper (elisp program); wrapper
which allows to change source of existing elisp program (configuration)?

How would you implement such a wrapper? Any suggestions? Would you suggest
to investigate how does work `customize-variable'? What else?



Andrey

Re: Tool for writing thin wrappers for changing existing elisp configurations

[Andreas Röhler]

Am 07.04.2014 20:40, schrieb Andrey Tykhonov:
>
> Hi List,
>
> is there any way to change configuration files by means of elisp functions?
> Which of them may help?
>
> For example, there are such lines in the ~/.gnus.el (but please note that
> that question is not about Gnus):
>
> #+begin_src elisp
> (setq nnmail-split-fancy
>        '(|
>          (: nnmail-split-fancy-with-parent )
>          (any "help-gnu-emacs@gnu\\.org" "help-gnu-emacs")
>          (any "emacs-devel@gnu\\.org" "emacs-devel")
>          "mail.misc"))
> #+end_src
>
> I would like to write a thin wrapper, interactive elisp function, which
> will be able to append new entry to the `nnmail-split-fancy'.
>
> When I will call that function (M-x add-nnmail-split-fancy-entry) then I'll
> be prompted for email address and imap folder (let 'any' will be
> hard-coded). Thus such command execution:
>
> M-x add-nnmail-split-fancy-entry RET emacs-orgmode@gnu.org RET
> emacs-orgmode RET
>
> will change configuration of the mentioned lines to the following:
>
> #+begin_src elisp
> (setq nnmail-split-fancy
>        '(|
>          (: nnmail-split-fancy-with-parent )
>          (any "help-gnu-emacs@gnu\\.org" "help-gnu-emacs")
>          (any "emacs-devel@gnu\\.org" "emacs-devel")
>          (any "emacs-orgmode@gnu\\.org" "emacs-orgmode")
>          "mail.misc"))
> #+end_src
>
> Yes, of course, I can just open ~/.gnus.el and add such entry. And of
> course I can change via M-x customize-variable RET nnmail-split-fancy RET.
>
> But this question is not about *how* to change existing elisp configuration
> but about a tool. I wonder: is there any elisp tool (package, functions
> etc) which allows to write such a thin wrapper (elisp program); wrapper
> which allows to change source of existing elisp program (configuration)?
>
> How would you implement such a wrapper? Any suggestions? Would you suggest
> to investigate how does work `customize-variable'? What else?
>
>
>
> Andrey
>
>

You could have a batch file calling Emacs to change existing file(s) as you can change this files calling other programs.
Also loading a certain init file might be an option, keeping several init-files.

Emacs init files are in Emacs lisp as others. Don't see anything special so far when changing it.

HTH,

Andreas

Re: Tool for writing thin wrappers for changing existing elisp configurations

[Andreas Röhler]

Am 10.04.2014 01:55, schrieb Andrey Tykhonov:

>
> Yes, but I want to have only one init-file and change by means of program
> (change a program by means of a program).
>

you can have in your init file something like that pseudo-code:

(finde-file...
search-and-replace..

reload-that-buffer

etc.

Or write

(cond (first-condition
        (load-or-just-find .... (and change?)

Re: Tool for writing thin wrappers for changing existing elisp configurations

[Suvayu Ali]

On Mon, Apr 07, 2014 at 09:40:35PM +0300, Andrey Tykhonov wrote:
> 
> I would like to write a thin wrapper, interactive elisp function, which
> will be able to append new entry to the `nnmail-split-fancy'.

 [...chomp...chomp...chomp...]

> Yes, of course, I can just open ~/.gnus.el and add such entry. And of
> course I can change via M-x customize-variable RET nnmail-split-fancy RET.
> 
> But this question is not about *how* to change existing elisp configuration
> but about a tool. I wonder: is there any elisp tool (package, functions
> etc) which allows to write such a thin wrapper (elisp program); wrapper
> which allows to change source of existing elisp program (configuration)?

If you don't want to use customize, maybe see how it does it and base
your tool on that?  The only tool I know which does this is customize.

Hope this helps,

-- 
Suvayu

Open source is the future. It sets us free.