Re: ox-bibtex.el -- how to join sequential citations

[Eric Schulte <schulte.eric@gmail.com>]

Nicolas Goaziou <n.goaziou@gmail.com> writes:

> Hello,
>
> Feng Shu <tumashu@gmail.com> writes:
>
>> Eric Schulte <schulte.eric@gmail.com> writes:
>>
>>> When exporting multiple sequential citations e.g., cite:foo cite:bar
>>> etc... I would like to see something like the following (latex used for
>>> this example) "\cite{foo, bar}", but instead I'm getting "\cite{foo}
>>> \cite{bar}", which leads to poorly formed PDFs (a similar thing happens
>>> for HTML export).
>>
>> May be you should use \cite{foo, bar} directly in org file.
>
> That was, indeed, the original way to handle citations in the former
> org-export-bibtex.el. It is still supported in both LaTeX, obviously,
> and HTML (which will split the above among two anchors).
>
> "cite" link support was added later, and is lacking in this area.
>
>>> My question is how best to fix this, should I write a filter function,
>>> or does the export engine already have processes in place to handle
>>> these sorts of export context issues?
>
> At the user level, a filter is definitely the way to go.
>

Thanks, the following seems to be working.  Perhaps the filter function
should be added to ox-bibtex.el?

    (defun org-bibtex-group-citations (text backend info)
      "Convert begin/end{verbatim} to begin/end{Verbatim}.
      Allows use of the fancyvrb latex package."
      (with-temp-buffer
        (insert text) (goto-char (point-min))
        (cond
         ((org-export-derived-backend-p backend 'latex)
          (while (re-search-forward
                  "\\\\cite{\\([^[:space:]\n\r]+\\)}[[:space:]\n\r]*\\\\cite{"
                  nil t)
            (replace-match "\\\\cite{\\1,")
            (goto-char (point-min))))
         ((org-export-derived-backend-p backend 'html)
          (while (re-search-forward
                  "\\(#[[:alnum:]]+\">[0-9]+<\/a>\\)\\][[:space:]\n\r]*\\[\\(<a href=\"#[[:alnum:]]+\">[0-9]+<\/a>\\)"
                  nil t)
            (replace-match "\\1,\\2")
            (goto-char (point-min)))))
        (buffer-string)))

    (add-to-list 'org-export-filter-final-output-functions
                 'org-bibtex-group-citations)

Cheers,

>
> Though, it is an interesting feature to implement in ox-bibtex.el. One
> idea would be to write another parse-tree filter function which would
> change cite links into \cite{...} commands and consecutive cite links
> into \cite{..., ...} commands.
>
> This would also allow us to get rid of both `org-html-link' and
> `org-latex-link' advices, as no more cite link would be left in the
> parse tree anyway.
>
> What do you think?
>
>
> Regards,

-- 
Eric Schulte
https://cs.unm.edu/~eschulte
PGP: 0x614CA05D