Re: [Emacs-diffs] master d48e07a: * lisp/simple.el (next-error-find-buffer-function): New defcustom.

[Dmitry Gutov]

On 2/22/18 12:04 AM, Stefan Monnier wrote:
> > +(defcustom next-error-find-buffer-function nil
>
> Why make it a defcustom rather than a defvar?

I think we'll want to provide a set of predefined functions in the 
future, for the user to choose one from.

> > +   (when next-error-find-buffer-function
> > +     (funcall next-error-find-buffer-function avoid-current
> > +                                              extra-test-inclusive
> > +                                              extra-test-exclusive))
>
> Could you arrange for the default value of this new *-function var not
> to be nil so we can modify it with add-function?

Personally, I don't really expect this variable to be modified 
programmatically. And if it is, most likely not in a "function 
combination" fashion.

But, of course, I might be wrong.