In LaTeX code I can have:
Lorem ipsum dolor sit amet, consectetur
\begin{comment}
adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation
\end{comment}
ullamco laboris nisi ut aliquip ex ea commodo consequat.
If I use comment-region (in a script) to comment the comment environment in la LaTeX code i obtain:
Lorem ipsum dolor sit amet, consectetur
%% \begin{comment}
%% adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
%% Ut enim ad minim veniam, quis nostrud exercitation
%% \end{comment}
ullamco laboris nisi ut aliquip ex ea commodo consequat.
This is not good because LaTeX interpret the empty line(s) (outside of comment environment) as a paragraph break.
My question is: Can I make comment-region comment empty lines?
I tried customizing (let-bind) the comment-syle variable but all the options I've seen do not comment empty lines.
An alternative could be a "built-in" (otherwise I already know how to make this funcion by myself) function that let me append a string on every line of a region (not a triangle). Remember, I need to do it programmatically.