mhex.sty

% !TeX encoding = UTF-8
% For the most current version, see https://github.com/supermihi/latex
\NeedsTeXFormat{LaTeX2e}[2011/06/27]
\RequirePackage{expl3,xparse,l3keys2e}
\ProvidesExplPackage{mhex}{2014/10/22}{5}{Defines exercise and solution environments with the ability to switch solution output on or off.}
\RequirePackage{etoolbox}
\RequirePackage{xspace}
\RequirePackage[inline]{enumitem}
\RequirePackage{amsfonts,amssymb}
\setlist[enumerate,1]{label=\alph*)}
\setlist[enumerate,2]{label=\arabic*.}
\RequirePackage{multicol}
\RequirePackage{xcolor}
% multi-column lists for small subexercises
\SetEnumitemKey{columns}{
  itemsep=1\itemsep,
  parsep=1\parsep,
  before=\begin{multicols}{\ifstrempty{#1}{2}{#1}},
  after=\raggedcolumns\end{multicols}
}
% ======================================================================================== %
% ========================= exercise and solution environments =========================== %
% ======================================================================================== %

\cs_new:Nn \l_mhex_exheader:n {
  \par\medskip
  \noindent{\textbf{\textsf{#1}}}
  \par
}

\keys_define:nn { mhexerciseenv } {
  points .tl_set:N = \l_mhex_curexpoints,
  points .value_required:,
  title  .tl_set:N = \l_mhex_curextitle,
  title  .value_required: ,
}
\newcounter{mhexercise}
\defcounter{mhexercise}{0}
\renewcommand\themhexercise{
  \tl_if_empty:NTF \l_mhex_sheetno {} {\l_mhex_sheetno.}
  \arabic{mhexercise}
}
\DeclareDocumentEnvironment
  {exercise}
  {o}
  {
    \keys_set:nn {mhexerciseenv} {points=,title=,}
    \IfValueTF
      {#1}
      {\keys_set:nn {mhexerciseenv} {#1}}
      { }
    \refstepcounter{mhexercise}
    \l_mhex_exheader:n
      {
        \l_mhex_exercisetext{}~\themhexercise
        \tl_if_empty:NTF \l_mhex_curextitle  {} {~\textendash{}~\l_mhex_curextitle}
        \tl_if_empty:NTF \l_mhex_curexpoints {} {~(\l_mhex_curexpoints{}~\l_mhex_pointstext)}
      }
    \label{mhexref\arabic{mhexercise}}
    \nopagebreak[4]
  }
  {\par\smallskip}

\keys_define:nn { mhexsolutionenv } {
  points .tl_set:N = \l_mhex_cursolpoints,
  points .value_required:,
}
\DeclareDocumentEnvironment
  {solution}
  {o}
  {
    \keys_set:nn {mhexsolutionenv} {points=,}
    \IfValueTF
      {#1}
      {\keys_set:nn {mhexsolutionenv} {#1}}
      { }
    \bool_if:NTF
      \l_mhex_solution
      {
        \l_mhex_exheader:n{
          \l_mhex_solutiontext{}~
          \ref{mhexref\arabic{mhexercise}}
          \tl_if_empty:NTF
            \l_mhex_cursolpoints
            {}
            {~(\l_mhex_cursolpoints{}~\l_mhex_pointstext)}
        }
      }
      {
        \par\vspace*{0pt}
        \setbox\z@\vbox\bgroup
      }
  }
  {
    \bool_if:NTF
      \l_mhex_solution
      {}
      \egroup
  }

% ======================================================================================== %
% ======================= Options for \exerciseSetup ===================================== %
% ======================================================================================== %

\keys_define:nn { mhex } {
  sheetnumber .tl_set:N = \l_mhex_sheetno,
  solution        .bool_set:N = \l_mhex_solution,
  exam            .bool_set:N = \l_mhex_exammode,
}

% defaults
\keys_set:nn { mhex } {
  sheetnumber = 1,
  solution    = false,
  exam        = false,
}

\cs_new:Npn \exerciseSetup #1 {
  \keys_set:nn { mhex } { #1 }
  \bool_if:NTF
    \l_mhex_exammode
    {\tl_set:Nn \l_mhex_sheetno {}}
    {}
}

% ======================================================================================== %
% ======== Bilingual Setup: Defining Captions in German and English ====================== %
% ======================================================================================== %

\cs_new:Nn \l_mhex_addcaption:Nnn {
  % add a bilingual text element.
  % First argument is the name, second the german, third the english text.
  % The text element will be accessible as \l_mhex_#1text.
  \gappto \captionsenglish { \tl_set:cn {l_mhex_#1text} {#3} }
  \gappto \captionsgerman  { \tl_set:cn {l_mhex_#1text} {#2} }
  \gappto \captionsngerman { \tl_set:cn {l_mhex_#1text} {#2} }
}

\l_mhex_addcaption:Nnn {exercise}  {Aufgabe}  {Exercise}
\l_mhex_addcaption:Nnn {exercises} {Aufgaben} {Exercises}
\l_mhex_addcaption:Nnn {solution}  {Lösung~zu~Aufgabe}   {Solution~to~Exercise}
\l_mhex_addcaption:Nnn {points}    {Punkte}   {points}
\l_mhex_addcaption:Nnn {part}      {Teil}     {part}
\l_mhex_addcaption:Nnn {parts}     {Teile}    {parts}

\DeclareDocumentCommand
  \mhexCaption
  { m m }
  { \AtBeginDocument{
      \tl_set:cn {l_mhex_#1text} {#2}
    }
  }
\AtBeginDocument{
  % renew the \mhexCaption command to immediately change captions after preamble
  \RenewDocumentCommand
    \mhexCaption
    { m m }
    {\tl_set:cn {l_mhex_#1text} {#2}}
  % ensure that babel or polyglossia are loaded
  \@ifpackageloaded{babel}{}
  {\@ifpackageloaded{polyglossia}{}{\PackageError{mhex}{babel~or~polyglossia~must~be~loaded!}}}
  \@ifpackageloaded{cleveref}{
    \crefname{mhexercise}{\l_mhex_exercisetext}{\l_mhex_exercisestext}
    \crefname{enumi}{\l_mhex_parttext}{\l_mhex_partstext}
  }
}

\ProcessKeysOptions{ mhex }