how to replace old-style backquotes (was: Re: Revert Emacs to version supporting cedet backticks?)

[Gregor Zattler]

Hi Tassilo,
* Tassilo Horn <tassilo@member.fsf.org> [21. Dec. 2010]:
> I don't think backticks are a problem, but only the old-style stuff
> deprecated for more than a decade had a bug in the current emacs bzr
> HEAD.
> 
>   `(foo ,tab-width) ;; new style. ok!
>     ==> (foo 2)
> 
>   (` (foo (, tab-width))) ;; old style. had a bug, but works for me...
>     ==> (foo 2)
> 
> I use a very recent Emacs version, so it seems that the bug is already
> fixed.
> 
> But it's still a very good idea to replace the old-style
> backquotes/backticks.

I have no clue about elisp but want to replace old-style with
new-style backquotes in old code I use.

Can this reliable be done by shortening every occurrence of 
(¸ like this:

  "(` ...)"  --> "`..."

and every comma-marked item like this:

  "(, ...)"  --> ",..."

or

  "(,@ ...)" --> ",@..."

?  If so the replacement could be done efficiently via a set of
Emacs macros (or elisp which I'm not capable of writing).

Or is it more complex than that?  E.g. does it matter how these
are nested or does the correct replacement depend on the actual
code (here represented as three dots)?


Ciao, Gregor
-- 
 -... --- .-. . -.. ..--.. ...-.-