Hi
To wrap up the discussion, the solution is
- for pdflatex:
#+begin_src org
* \\phi wraps
:PROPERTIES:
:ALT_TITLE: \texorpdfstring{$\backslash\psi$}{\textbackslash psi} wraps too
:END:
#+end_src
i.e. no math in the PDF outline
- for LuaLaTex you can also:
#+begin_src org
* \\phi wraps
:PROPERTIES:
:ALT_TITLE: \texorpdfstring{$\backslash\psi$}{\textbackslash Ψ} wraps too
:END:
#+end_src
You need
As in LaTeX, you need to add some "magic" to keep the underlying LaTeX
compiler happy.
Best, /PA
On Sun, 16 Nov 2025 at 18:08, Ihor Radchenko <[email protected]> wrote:
> Pedro Andres Aranda Gutierrez <[email protected]> writes:
>
> > More facts about why lualatex-math vs unicode-math...
> >
> > When I use fontspec+unicode-math with lualatex, what I see is the
> following
> > [image: image.png]
> > Look at the outline, please.
> > Now, replacing unicode-math with lualatex-math:
> > [image: image.png]
> > The outline is not perfect, but certainly 'better' (if you understand
> what
> > I mean).
>
> Well. That's far from "didn't generate a PDF".
> I also observed that the outline has issues with math.
> I feel like you are trying to find a workaround for something that can
> be fixed. Try the attached file and remember that we have
> `org-latex--section-backend' where we can program the same behavior.
>
> Here is what I got from LLM (this time, it was a good response)
>
> The following
> \section[$\backslash$\texorpdfstring{\(\psi\)}{psi} should
> wrap]{$\backslash$\texorpdfstring{\(\phi\)}{phi} wraps}
> this does not seem to work in lualatex. I get
> 灳椠 should wrap
>
> # LLM response
> What you are seeing is a double round-trip:
>
> 1. The optional short title “=$\backslash\texorpdfstring{(\psi)}{psi}
> should wrap=” is processed by LaTeX first.
> 2. =\backslash= expands to =\textbackslash{}= and finally to a text-mode
> backslash character (U+005C).
> 3. When hyperref converts the bookmark string to PDFDocEncoding or UTF-16
> it receives a literal backslash, followed immediately by the math command
> =\psi=. PDF bookmarks do not understand math, so the character produced in
> position π comes out of the encoding tables as the Unicode code-point π,
> and π is what you get in the encoding tables as “灳” … when it is actually
> meant to remain as literal text, you must keep it away from math mode.
>
> With pdfTeX this accidently looks “right” because pdfTeX bookmarks use an
> old 8-bit PDFDocEncoding table; with Lua- and Xe-TeX (=unicode= option) the
> output is shown in UTF-16 and suddenly every 8-bit character is visible.
>
> Fix: keep the bookmark text completely free of math mode or any macro that
> hyperref must expand in an expansion-only context:
>
> #+begin_src latex
> \section[\textbackslash psi should wrap]{% <-- printable part for the
> outline
> $\backslash\phi$ wraps% <-- printed heading
> }
> #+end_src
>
> or, if you really want the Greek letter in the outline, supply the
> /Unicode/ character directly:
>
> #+begin_src latex
> \section[\textbackslash ψ should wrap]% literal ψ (U+03C8)
> {$\backslash\phi$ wraps}
> #+end_src
>
> and, if you want exactly the same text as in the full heading, protect the
> math or let =\texorpdfstring= replace the whole fragment:
>
> #+begin_src latex
> \section[\texorpdfstring{\textbackslash\ensuremath{\psi}}{\textbackslash
> psi} should wrap]%
> {$\backslash\phi$ wraps}
> #+end_src
>
> Remember: anything that appears in the optional short-title argument must
> be either
> - ordinary text that can be converted to Unicode, or
> - inside =\texorpdfstring= with the /second/ argument being exactly the
> plain-text you want in the outline.
>
> Using =\texorpdfstring= inside the optional argument itself fails because
> hyperref tries to expand it once more and sees the literal =\backslash=
> again—hence the garbled result you observed.
>
>
> --
> Ihor Radchenko // yantar92,
> Org mode maintainer,
> Learn more about Org mode at <https://orgmode.org/>.
> Support Org development at <https://liberapay.com/org-mode>,
> or support my work at <https://liberapay.com/yantar92>
>
--
Fragen sind nicht da, um beantwortet zu werden,
Fragen sind da um gestellt zu werden
Georg Kreisler
"Sagen's Paradeiser" (ORF: Als Radiohören gefährlich war) => write BE!
Year 1 of the New Koprocracy
