Re: [Orgmode] LaTeX export of section links

[Carsten Dominik]

On Nov 20, 2009, at 4:14 PM, Francesco Pizzolante wrote:

> Hi Carsten,
>
> > > --8<---------------cut here---------------start------------->8---
> > > * First
> > > :PROPERTIES:
> > > :CUSTOM_ID: heading-a
> > > :END:
> > >
> > > Hello Toto!
> > >
> > > * Second
> > > # <<heading-b>>
> > >
> > > Hello Tata!
> > >
> > > * Third
> > > #+CUSTOM_ID: heading-c
> > >
> > > Hello Titi!
> > >
> > > * Fourth
> > > #+ID: heading-d
> > >
> > > Hello Tete!
> > >
> > > [[heading-a]]
> > > [[heading-b]]
> > > [[heading-c]]
> > > [[heading-d]]
> > > --8<---------------cut here---------------end--------------->8---
> > >
> > > Which give the following LaTeX code:
> > >
> > > --8<---------------cut here---------------start------------->8---
> > > \section{First}
> > > \label{sec-1}
> > > \label{heading-a}
> > >
> > >
> > > Hello Toto!
> > >
> > > \section{Second}
> > > \label{sec-2}
> > > \label{heading-b}
> > >
> > >
> > > Hello Tata!
> > >
> > > \section{Third}
> > > \label{sec-3}
> > >
> > >
> > > Hello Titi!
> > >
> > > \section{Fourth}
> > > \label{sec-4}
> > >
> > >
> > > Hello Tete!
> > >
> > > \hyperref[sec-1]{heading-a}
> > > \hyperref[sec-2]{heading-b}
> > > \hyperref[sec-3]{heading-c}
> > > \hyperref[sec-4]{heading-d}
> > > --8<---------------cut here---------------end--------------->8---
> > >
> > > The third and fourth cases are very elegant as they use only  
> > > aliases (which
> > > are dropped from the LaTeX code).
> >
> > Third and forth are non-existent syntax in Org, these lines are  
> > just treated
> > as comments and are removed during export.
>
> OK. But the information in these 2 comments is correctly used to  
> replace the
> alias (heading-c and heading-d) with the label generated by org  
> during the
> export. See the last 2 references in my example: these references  
> are correct.
> They thus have been correctly processed from heading-c and heading-d  
> to sec-3
> and sec-4... these comments are thus not simply removed... right?

This is only by chance, because a simple text search does match these  
two lines.
if you'd happen to have the string headline-a anywhere in the file,  
the link would point to the enclosing section.

> In the case of the :CUSTOM_ID: property, the property is also used  
> to convert
> the alias to the label (heading-a to sec-1) but additionally an  
> extra label
> (heading-a) is created and not used.
>
> That's why, when creating references to sections I found the # 
> +CUSTOM_ID very
> elegant... But apparently I don't have to use such syntax...

Not if you want to have reliable links, no.

- Carsten


> I wanted to know the recommended way of doing references...
>
> Thanks a lot for your help.
>
> Francesco

- Carsten