The default of the defcustom can also be the result of a function call
(like `format', etc). Basically everything that returns a string will do.


On 19 January 2014 10:36, Vibhav Pant <vibhavp@gmail.com> wrote:

>
> Bozhidar Batsov writes:
>
> > Seems to me that there should be just a defcustom `url-user-agent' and it
> > should be used always. By default it should have whatever value it
> > currently has and users will be able to customise it.
> The function url-http-user-agent-string generates a user agent by
> concatinating url-package-name and url-package-version. So the defcustom
> would have to be a function or a sexp, making things a little confusing
> for new users.
>
> --
> Vibhav Pant
> vibhavp@gmail.com
>