Re: [External] : Re: Default custom file was: Re: Propose to add setup-wizard.el to ELPA

[Tim Cross <theophilusx@gmail.com>]

Drew Adams <drew.adams@oracle.com> writes:

>> From your response, there are a couple of additional
>> points I'd like to make to clarify some things.
>> 
>> The reason I don't think just setting the custom file
>> to some value really covers the full scope of the
>> change is because in addition to that change, it will
>> also be necessary to add code to make emacs load that file.
>
> I assume you mean load that file _automatically_,
> since users can (and do) already load it in their
> init files.
>
> Automatically loading `custom-file', if it isn't
> loaded by the init file (and any code that file
> loads etc.), is not a hard requirement.
>
> It's something that could easily be done, but it's
> not _required_ to advance the aim of getting more
> users aware of and using `custom-file'.
>
>> This means either the timing of loading that file would then
>> be up to Emacs or we would have to add some other switch to disable
>> automatic loading to restore user control over loading that file.
>
> Yes.  But I think that can be as simple as what
> I suggested:
>
> 1. Automatically load `custom-file' (provided it's
>    not the same as the init file) immediately after
>    the init file is loaded.
>
>    (We already automatically load other files if
>    they exist - site-lisp.el etc.)
>
> 2. Provide users with a way to inhibit automatic
>    loading if they need/want to do that.
>
> (Those users who want to do everything in their
> init file are not involved in this - they'd
> just set `custom-file' to their init file.)
>
>> So already the 'simple' change proposal has added additional complexity
>> (albeit small). 
>
> As I say, automatic loading isn't a requirement.
> It's a feature.  And with #2 it's optional.
>
> (One way to realize #2 would be with a user
> option.  We could discuss its default value.)
>
>> There could be other corner cases I've not thought of as
>> well, especially once we add a new 'toggle' for the loading behaviour.
>
> If we're really worried about that, then we
> just don't provide any such automatic loading.
>
> I don't expect problems, but automatic loading
> isn't a requirement.  Nothing in the general
> aim and proposed solutions requires it.
>
> Without it, users would just be responsible for
> loading `custom-file' - like now.  Not a big
> deal, but I think it might help users to provide
> it (new users especially).
>
>> The change management aspects I referred to are perhaps a little subtle
>> and are certainly hard to quantify. However, it is often way too easy to
>> underestimate the impact of such change and identify what needs to be
>> done to mitigate it. This impact can be especially hard to recognise
>> when you are invested in the change.
>
> I don't disagree with that general point.
>
> I don't foresee any complications, but I'm
> _not_ really invested in Emacs providing the
> ability to automatically load `custom-file'.
>
>> Things which need to be considered
>> (some of which have been mentioned) include
>> 
>> - dealing with impact on existing users
>> - updating documentation, including manuals, howtos, faqs etc
>> - managing the confusion that will arise due to the amount of existing
>>   and easily found information out there (stack overflow, reddit, wikki,
>>   blogs, books etc) which will be out of date and will likely cause more
>>   confusion.
>
> Sure.
>
>> Just dealing with the first one will likely result in the final solution
>> being more complex than simply setting a default custom file value,
>> which in turn will make the other points more substantial to deal with.
>
> I don't think so, but I can't prove you're wrong.
>
> Suppose we don't offer automatic loading.
> If you don't load `custom-file' (from your
> init file or in some other way) then it doesn't
> get loaded.  End of story.
>
> Or suppose we offer it, but by way of a user
> option that by default is off (no autoload).
>
> IOW, no change from what we do now, in this
> respect (no autoloading of `custom-file').
>
> In that case, the change is just to default
> `custom-file' to a standard location, not to
> nil.  Now reread your paragraph of things that
> need to be considered.  Not a big deal in this
> case, right?
>
> I wouldn't be completely happy with that
> solution, but it would still be an improvement.
>
> As I said, it would even be a (small)
> improvement if Emacs would just come out and
> recommend to users to use `custom-file',
> instead of just warning them, in the init-file
> template-comment, not to edit the inserted
> generated code.
>
> I'd hope that we go further than that, but
> even that would help.
>
>> The above are some of the reasons I think it may be misleading to
>> characterise the proposal as something simple. 
>
> "The proposal" is really a set/hierarchy of
> proposals, from trivially simple, with little
> effect (and I hope little controversy), to
> something that includes possibly automatically
> loading `custom-file'.
>
> I hope you'll agree that the mere change to
> defaulting `custom-file' to a file name isn't
> complicated in its implications, and it should
> not be controversial.
>
> All of what would happen in that case already
> happens, if a user sets `custom-file' to a
> file name.  If no one loads that file, or if
> that file remains nonexistent or empty, we're
> in no-op land.
>
> Even users who only want to use their init
> file for customizations wouldn't be impacted.
> No-op.
>
>> However, I would be in support if I thought
>> this was an actual problem needing to be addressed.
>
> Maybe think of it as what we have now: offering
> `custom-file', but just making use of it a bit
> more visible and likely.  Instead of thinking
> "problem" and "solution", maybe just think that
> it might help more users to take advantage of
> `custom-file'.
>
>> TO me, it really does feel more like a solution in search of a problem
>> or at the very least, a change which will result in non-trivial effort
>> (at various levels) when there is little evidence it is really required.
>
> I understand that you feel that.  I think your
> fears are unnecessary.  Take out the "automatic
> loading" feature from your consideration, and
> see how fearful you still are.

Hi Drew,

we seem to be mis-communicating here or I'm just not being clear enough.
One last attempt and then I'll leave it alone.

My understanding of your suggestion is to set custom-file to some
default location rather than nil e.g. .emacs.d/custom.el. You suggest
that is all which is required and that no automatic loading would need
to be added. I reject this as automatic loading would be absolutely
necessary to retain existing behaviour.

If all we do is set custom-file to a default location, custom will stop
working between sessions because nothing will load those settings. This
significantly changes behaviour. To keep the same behaviour, either all
users who now just use custom with custom-file set to nil would need to
add a load statement OR emacs will have to automatically load that file.

Requiring users add a load statement to their initialisation file to
ensure custom settings work across sessions is a bad design and would
impact too many existing users.

If we change the default setting of custom-file from nil to a
default file location, there will need to be code added to Emacs to load
that file at some point in the initialisation step. If we then also want
to retain the user's ability to control when this file is loaded, we
will also require a toggle to turn off that loading and allow the user
to do it. 

Claiming that all you are proposing is a change to the default value for
custom-file is inaccurate if you also want to claim no change in
behaviour.