Detecting section depth

Question

Is it possible for an environment to detect which sectioning level it is at?

I'm in the process of creating a package which defines a numbered environment of question/answer pairs, and I want to provide the option to customise which section level the numbers should be reset at, as well as whether the question/answer pairs should be included in the table of contents. The idea is for these Q/A pairs to form a parallel set of sectioning-like environments that won't interfere with the normal sectioning commands.

EDIT Perhaps a bit more context would be useful. I've been using a macro not unlike the one reproduced below to create question/answer environments in my assignments that would function similarly to sections, but have their own counters. This is such useful code that I'm trying to split it out into a package I can reuse, but I need to figure out a way to make the question environment figure out whether it's inside a section in order to set its numbering correctly as well as optionally put it in the table of contents and PDF outline/index.

% vim: ft=tex
% arara: lualatex
% arara: lualatex

\documentclass{scrartcl}

\usepackage{etoolbox}

\usepackage{fontspec}
\defaultfontfeatures{Ligatures=TeX}

\newlength{\questionbeforeskip}
\newlength{\questionafterskip}
\setlength{\questionbeforeskip}{1.0ex plus -1ex minus -0.25ex}
\setlength{\questionafterskip}{1ex plus 0.25ex}
\newlength{\answerskip}
\setlength{\answerskip}{0.25ex plus -0.125ex minus -0.125ex}

\addtotoclist{loq}
\newcommand{\listofloqname}{List of Questions}
\newcommand{\listofquestions}{\listoftoc{loq}}
\setuptoc{loq}{leveldown}

\newcounter{question}[section]

\newcommand{\questionautorefname}{question}
\newenvironment{question}
{
  \refstepcounter{question}%
  \addxcontentsline{loq}{subsection}{Question~\thequestion}
  \pdfbookmark[2]{Question~\thequestion}{question:\thesection.\thequestion}
  {{\par\vspace\questionbeforeskip \large Question~\thequestion.}\par}
  \begin{itshape}
}
{\end{itshape}\par\vspace\questionafterskip}

\usepackage[inline]{enumitem}
\setlist[enumerate]{label=(\alph*)}

% Sub-questions are represented as an enumerate
\newlist{subquestions}{enumerate}{3}
\setlist[subquestions]{leftmargin=*}
\setlist[subquestions,1]{label=\textup{\textbf{(\alph*)}}}
% Inline subquestions
\newlist{subquestions*}{enumerate*}{3}
\setlist[subquestions*]{itemjoin*={{, and }}}
\setlist[subquestions*,1]{label=\textup{\textbf{(\alph*)}}}

\newcommand{\qitem}[1]{\item{\textit{#1}}}
\newcommand{\qitemp}[1]{\qitem{#1}\\[0.5\parskip]}
\newcommand{\qitemq}[1]{\qitem{#1}\quad}

%% Penalties
\hyphenpenalty=2500
\tolerance=500
\widowpenalty=1500
\clubpenalty=1500

\usepackage{hyperref}
\hypersetup{
  colorlinks=false,
  hidelinks}
\usepackage[all]{hypcap}
\usepackage[noabbrev,capitalise]{cleveref}
\labelcrefformat{subfigure}{\textbf{(#2#1#3)}}

\begin{document}


\section{Osmosis and kinetics}

\begin{question}
  What is reverse osmosis? Describe a process which involves the use of reverse
  osmosis (use a diagram in your answer).
\end{question}

Answer blah

\begin{question}
  What are colloidal particles? What are the main processes that are used to
  remove colloidal particles from aqueous solutions?
\end{question}

Some other answer

\section{Organic chemistry / Natural gas processing}

\begin{question}
What are four ways of representing organic molecules such as alkanes?
\end{question}

\begin{question}
  Draw structural formula for the following compounds:
  \begin{subquestions}
    \item 3-methylnonane
    \item 3-ethylheptane
    \item 2-methyloctane
  \end{subquestions}
\end{question}

\begin{subquestions}
  \item Answer 1
  \item Answer 2
  \item Answer 3
\end{subquestions}

\end{document}

So far what I've managed to extract into a package is the following. The PGFKeys switch to choose which section level to reset the question numbering is a bit clumsy, so I will probably replace it with something simpler (maybe xkeyval?). I'm using this exercise as an attempt to learn the ropes at creating a functional package that might be useful to someone other than myself. To use this package in the previous example, you'd have to load it with \usepackage{questions} and remove the duplicated code.

\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{questions}
  [2017/11/17 v0.1 Assignment Questions]
\RequirePackage{etoolbox}
\RequirePackage{pgfopts}
\RequirePackage{chngcntr}
\RequirePackage[inline]{enumitem}
% Question counter
\newcounter{question}
% Define option keys with PGFKeys
\pgfkeys{/questions/.cd}
\pgfkeys{/questions/reset/.cd,
  .is choice,
  part/.code={%
    \counterwithin*{question}{part}
  },
  chapter/.code={%
    \counterwithin*{question}{chapter}
  },
  section/.code={%
    \counterwithin*{question}{section}
  },
  subsection/.code={%
    \counterwithin*{question}{subsection}
  },
  subsubsection/.code={%
    \counterwithin*{question}{subsubsection}
  },
  paragraph/.code={%
    \counterwithin*{question}{paragraph}
  },
  subparagraph/.code={%
    \counterwithin*{question}{subparagraph}
  },
  none/.code={%
    \counterwithout*{question}{section}
  },
}
% \pgfkeys{/questions/reset/.default = paragraph}

\newcommand{\questions@setdefaults}{
  \pgfkeys{/questions/.cd,
    reset=section,
  }
}

\newcommand{\questionset}[1]{\pgfkeys{/questions/.cd,#1}}
\questions@setdefaults
\ProcessPgfOptions{/questions}

\newlength{\questionbeforeskip}
\newlength{\questionafterskip}
\setlength{\questionbeforeskip}{1.0ex plus -1ex minus -0.25ex}
\setlength{\questionafterskip}{1ex plus 0.25ex}
\newlength{\answerskip}
\setlength{\answerskip}{0.25ex plus -0.125ex minus -0.125ex}

\addtotoclist{loq}
% \newcommand{\listofloqname}{List of Questions}
% \newcommand{\listofquestions}{\listoftoc{loq}}
% \setuptoc{loq}{sectionatlist}


\newenvironment{questionenv}
{
  \refstepcounter{question}%
  % \addxcontentsline{loq}{subsection}{Question~\thequestion}
  % \pdfbookmark{Question~\thequestion}{question:\thequestion}
  {{\par\vspace\questionbeforeskip Question~\thequestion.}\par}
  \begin{itshape}
}
{\end{itshape}\par\vspace\questionafterskip}

\newlist{subquestions}{enumerate}{3}
\setlist[subquestions]{leftmargin=*}
\setlist[subquestions,1]{label=\textup{\textbf{(\alph*)}}}
% Inline subquestions
\newlist{subquestions*}{enumerate*}{3}
\setlist[subquestions*]{itemjoin*={{, and }}}
\setlist[subquestions*,1]{label=\textup{\textbf{(\alph*)}}}

\endinput

The next MWE illustrates how the questions package is intended to be used. Setting the restart option changes where the questions are numbered from (it defaults to section).

% vim: ft=tex

% arara: lualatex
% arara: lualatex

\documentclass{scrartcl}

%% KOMA options
\KOMAoption{cleardoublepage}{empty}
\KOMAoption{DIV}{10}
\KOMAoption{draft}{false}
\KOMAoption{fontsize}{10pt}
\KOMAoption{headings}{small}
\KOMAoption{paper}{a4}
\KOMAoption{parskip}{half}
\KOMAoption{twoside}{false}
\KOMAoption{captions}{signature}
\KOMAoption{titlepage}{false}
\KOMAoption{abstract}{false}

\usepackage{etoolbox}

\usepackage{fontspec}
\defaultfontfeatures{Ligatures=TeX}

\usepackage[reset=none]{questions}

%% Penalties
\hyphenpenalty=2500
\tolerance=500
\widowpenalty=1500
\clubpenalty=1500

\usepackage{hyperref}
\hypersetup{
  colorlinks=false,
  hidelinks}
\usepackage[all]{hypcap}
\usepackage[noabbrev,capitalise]{cleveref}
\labelcrefformat{subfigure}{\textbf{(#2#1#3)}}

\begin{document}


\section{A section}

\begin{questionenv}
The question in a section
\end{questionenv}

\subsection{A subsection}

\begin{questionenv}
The question in a subsection
\end{questionenv}

\begin{questionenv}
Another question in a subsection
\end{questionenv}

\subsubsection{A subsubsection}

\begin{questionenv}
The question in a subsubsection
\end{questionenv}

\begin{questionenv}
Another question in a subsubsection
\end{questionenv}

\subsubsection{A subsubsection}

\begin{questionenv}
The question in a subsubsection
\end{questionenv}

\begin{questionenv}
Another question in a subsubsection
\end{questionenv}

\subsection{Another subsection}

\begin{questionenv}
Another question in a subsection
\end{questionenv}

\begin{questionenv}
What is this question?
\end{questionenv}

\section{Another section}

\begin{questionenv}
Another question in another section
\end{questionenv}

\begin{questionenv}
Another question in another section
\end{questionenv}

\subsection{A subsection}

\begin{questionenv}
The question in a subsection
\end{questionenv}

\begin{questionenv}
Another question in a subsection
\end{questionenv}

\begin{questionenv}
Another question in a subsection
\end{questionenv}

\subsubsection{A subsubsection}

\begin{questionenv}
The question in a subsubsection
\end{questionenv}

\begin{questionenv}
Another question in a subsubsection
\end{questionenv}

\subsubsection{A subsubsection}

\begin{questionenv}
The question in a subsubsection
\end{questionenv}

\begin{questionenv}
Another question in a subsubsection
\end{questionenv}

\end{document}

Answer 1

I don't think that LaTeX provides an automatic way of doing this, however, you can hack one easily enough. All sections, subsections, etc are created using \@startsection. This macro expects 6 arguments, the second of which is an "index" for the section depth (\@startsection compares this with secnumdepth to decide whether to add a toc entry etc). Using \pretocmd from the etoolbox you can make \@startsection "save" this index for future use:

\documentclass{article}
\usepackage{etoolbox}

\makeatletter
\def\currentsection{0}% initialise
\pretocmd\@startsection{\def\currentsection{Current section index: #2}}{}{}
\makeatother

\begin{document}

\section{A section}
\currentsection

\subsection{A subsection}
\currentsection

\subsubsection{A subsubsection}
\currentsection

\section*{A starred section}
\currentsection

\subsection*{A starred subsection}
\currentsection

\subsubsection*{A starred subsubsection}
\currentsection

\end{document}

This produces:

For other document classes you might have to change this a little but the idea should be the same. In practice, you'd probably just want to use

\pretocmd\@startsection{\def\currentsection{#2}}{}{}

after which you can do things like

\ifcase\currentsection% ignore 0, which should only happen with no sections
\or % stuff for sections
\or % stuff for subsections
....
\fi

Edit

As already mentioned, this might require tweaking with different document classes. For example, the KOMA-script scrartcl.cls redefines most of the LaTeX internals so unsurprisingly, and as noted in the comments, the code above does not work. KOMA-script does provide a \At@startsection hook but I can't see how to use this because, as far as I can see, there is no way for it to know which "section" it is in. This said, it turns out that scrartcl.cls replaces @\startsection with \scr@startsection so, much as above, one can use:

\pretocmd\scr@startsection{\def\currentsection{Current section index: #2}}{}{}

Be warned, however, that the KOMA documentation explicitly discourages changing macros like \scr@startsection as they don't guarantee not to changing them in future. Here is the full code - modulo the KOMA styling changes, the output is similar.

\documentclass{scrartcl}
\usepackage{etoolbox}

\makeatletter
\def\currentsection{0}% initialise
\pretocmd\scr@startsection{\def\currentsection{Current section index: #2}}{}{}
\makeatother

\begin{document}

\section{A section}
\currentsection

\subsection{A subsection}
\currentsection

\subsubsection{A subsubsection}
\currentsection

\section*{A starred section}
\currentsection

\subsection*{A starred subsection}
\currentsection

\subsubsection*{A starred subsubsection}
\currentsection

\end{document}