bug#57246: biblatex don't recognize video type entry

[Roland Winkler]

On Wed, Aug 17 2022, Lars Ingebrigtsen wrote:
> Cletip Cletip <clement020302@gmail.com> writes:
>
>> It's all in the object: biblatex does not recognize inputs of type "video".
>> I think that the bibtex-biblatex-entry-alist variable (and maybe
>> bibtex-biblatex-field-alist) should be modified
>
> Perhaps Roland has some comments here; added to the CCs.

I believe these are non-standard biblatex entries with incomplete
biblatex support.

In Emacs BibTeX mode the problem is here that all biblatex entry types
are defined via the rather "big" user variable
bibtex-biblatex-entry-alist.  So the idea is that users can customize
this variable and define additional entry types.  However, this is not a
very practical strategy.  From a technical perspective, there is still
bug#53606.  Also, as biblatex evolves, the default value of
bibtex-biblatex-entry-alist is continuously updated with each release of
Emacs.  (Usually this refers to small changes concerning biblatex entry
types that are already defined via this variable.)  However, if a user
customizes this variable in whatever way, she will miss the updated
default value when the next release of emacs is shipped.

I believe, these problems are not specific to BibTeX mode.  There are
several "big" user variables in Auctex where I am splicing my custom
elements into an alist instead of using the customize machinery.  This
is not a very user-friendly approach.

Often such "big" user variables are alists.  Sometimes I have been
wondering whether the customize machinery could provide special support
for alists that allows one to modify or add individual cons cells
without touching other cells that are part of the default value.  Then
if a new release of emacs uses updated values for such user variables,
there are less opportunities for how this may collide with individual
customizations.

Would that be useful?

In the present context, a simpler strategy would be to define a new user
variable bibtex-biblatex-extra-entry-alist that complements / overrides
the defaults in bibtex-biblatex-entry-alist.