Re: [PATCH] ox-latex.el: Unify in one single list Babel and Polyglossia languages alists

[Max Nikulin]

On 22/07/2022 21:07, Juan Manuel Macías wrote:
> Forget this. On second thought, I think that the option you proposed
> "#+LaTeX_Header: % \usepackage{babel}" is much better.
>
> (I don't know where my head was and I didn't remember there was a
> string-match, so your suggestion is the shortest way. However, the line
> would have to be (with arguments):
>
> #+LaTeX_Header: % \usepackage[something]{babel}
>
> or
>
> #+LaTeX_Header: % \usepackage[something]{polyglossia}
>
> or modify the regexp in org-latex-guess-babel/polyglossia-language.

It was you who suggested

    \documentclass[russian]{article}
    \usepackage{babel}

At least at first glance it works in texlive-2019 (Ubuntu-20.04), so it 
is not a feature from the latest release. Unless commented out,
"#+latex_header: \usepackage{babel}" may be considered as an instruction 
to add value of #+language: to \documentclass option. I do not expect 
that adjusted regexp will cause a problem.

> Anyway, whatever the choice, I would vote for Org not to load babel or
> polyglossia by default, and for the default option of the custom
> variable that handles that globally to be nil. For example, I'm in the
> group of users that load babel using an external preamble (a .tex or a
> .sty file or a 'latex-class'), and frankly I don't want to have to add a
> new line to all my documents to prevent Org from reloading babel for me
> and return an error on the compilation.

Doesn't the purpose of a custom variable is to set it to a suitable 
value in the init file making it unnecessary adding configuration to 
each org file? I did not expected that setting it to e.g. nil will be 
real burden for users like you.

My vote is to configure babel by default if it is possible to provide 
default preamble that allows reasonable quality of PDF for simple Org 
documents with no explicit configuration.

Ideally, the following should be possible out of the box. When no 
advanced features are involved, user should be able to just export 
document to e.g. having printed version of their notes during a meeting, 
to send a summary to the boss. etc. It should be possible for users 
completely ignorant in respect to LaTeX.

Likely language is not enough and e.g. paper size should be guessed 
(LC_PAPER?) as well.

If a document require careful tuning then a couple of extra lines in the 
org file or a couple of additional custom variables in the init file 
should not be a problem.