Re: general customize-like data editor?

[Eric Abrahamsen]

Ted Zlatanov <address@hidden> writes:

> Several times[1] I've wished for a general data editor.
>
> It would behave like Customize but at the data level. The closest I've
> found is `eieio-customize-object' from eieio-custom.el. The EIEIO
> facilities make a lot of sense for this, and I don't think it's a big
> burden for packages to map their *editable* structures to defclasses,
> even if they don't buy into it generally.
>
> So my questions are:
>
> 1) are there non-EIEIO field editors, based on alists or plists when you
> don't know all the fields in advance, but can specify their type? The
> use case here is "I have a data structure with integer keys x, y, z; all
> the rest should default to string editing."
>
> 2) inside Emacs, `eieio-customize-object' is only used by CEDET. Are
> there other packages that use it? Any experiences, positive or negative?

I've used it a grand total of once, and it works great. The code looks
like this:

(cl-defmethod ebdb-db-customize ((db ebdb-db))
  (require 'eieio-custom)
  (eieio-customize-object db))

(cl-defmethod eieio-done-customizing ((db ebdb-db))
  (setf (slot-value db 'dirty) t)
  (cl-call-next-method))

That's all I had to do! That plus :custom tags on the slot definitions.
The only thing I find a little awkward is that you end up having
semi-redundant information in the :type and :custom tags.

> 3) currently `eieio-customize-object' is focused on editing a single
> object. Are there table editors that would allow changing multiple
> objects? For instance the process environment editor in
> https://github.com/dgtized/list-environment.el could use that. The
> use case here is "I have a data structure with a list of strings I'd
> like to edit."

This example sounds like you're customizing a single object, with a
single slot, with a :type (list-of string) tag and a :custom (repeat
string) tag (see what I mean about semi-redundancy?). So far as I know,
this will work out of the box.

Actually editing multiple objects in one Customize buffer would probably
require new code.

Eric

> Clearly this parallels the Customize interface, which knows how to
> validate and edit things like '(repeat string) etc. so if there are ways
> to simply use that interface, that's probably easiest. But that doesn't
> solve editing multiples as in (3) and seems to have a lot of hard-coded
> behavior specific to customizing named variables. So I'm not sure what
> to do.
>
> Thanks
> Ted
>
>
> [1] https://github.com/vmware/govmomi/issues/646 and 
> https://github.com/dgtized/list-environment.el/issues/2 for instance