AucTeX - insert environment menu command

Question

I have a big LaTeX project divided in many files; the \documentclass statement and the preamble are in the main file, that in turn includes many (~20) other files, one for every chapter. One of the statements in the main file is \usepackage{paralist}, in order to use the environment compactdesc.

Visiting the main file, in the AucTeX LaTeX -> Insert Environment menu, compactdesc is listed; and M-Enter inside the environment inserts an \item and asks for the label of that item.

Visiting one of the included file, the lack of a \usepackage causes no inclusion of the compactdesc environment in the LaTeX -> Insert Environment menu list; and I don't like that.

Giving the command M-x LaTeX-environment followed by compactdesc, inserts in the file a \begin{compactdesc}-\end{compactdesc} couple, but M-Enter does not ask for the item label - and I would like to be able to enter the labels for every \item added.

I have tried with the local variables at the end of the file, inserting the lines

% Local Variables:
% mode: latex
% TeX-master: master.tex
% ispell-local-dictionary: "italian"
% End:

(where master is the main TeX file); but still LaTeX -> Insert Environment does not know about compactdesc.

How can I do, to have both 1) the environment compactdesc available and 2) AucTeX knowing about items of that environment having a label?

Thank you in advance for any help.

Answer 1

Well, the last suggestion did the magic... So I have to download the master file first and the included file second? No problem. Thank you, giordano, for your suggestions and your tolerance.

I experimented a little bit more. I added to the master file the local variable (at the end of the file) %%% mode: latex — that did the trick (in addition to the %%% TeX-master: "master" local variable in the included files).