Re: How to fix Emacs24 compiler warning w/o breaking code for previous versions

[David Kastrup <dak@gnu.org>]

Jambunathan K <kjambunathan@gmail.com> writes:

> Stefan Monnier <monnier@iro.umontreal.ca> writes:
>
>>> I've been working to address the elisp byte-compiler warnings thrown
>>> while compiling the current Org-mode head, and I do not know how to
>>> address cases where the byte-compiler insists on usage of a new feature
>>> not present in older Emacsen without breaking Org-mode support of those
>>> Emacsen.  I'm writing to ask for the "best practices" approach?
>>
>> IMNSHO:
>> - The simplest solution is to only support a single or a very limited
>>   number of Emacs versions.
>> - Another good one is to support many versions, only pay attention to
>>   warnings in the most recent supported version, and accept some warnings
>>   as "better have the warnings than break backward compatibility".
>> - The next best one is to do as above except that you additionally wrap
>>   the remaining warnings in `with-no-warnings' (and regularly remove
>>   those `with-no-warnings' to remind you of the problems you can't fix
>>   yet because of backward compatibility).
>> I strongly recommend against aiming to silence warnings on all the
>> supported Emacs versions.  It's a waste of time and leads to poor code
>> (e.g. ugly/brittle byte-compiler hacks, cc-bytecomp comes to mind, I'd
>> better stop here or I'll have nightmares again).
>
> I was hoping that there is an elisp equivalent for C-like
>
> #if emacs-version > a
>     do this
> #else
>     do that
> #endif

(if (version<= "21.0" emacs-version)

-- 
David Kastrup