1 files changed, 48 insertions, 25 deletions
diff --git a/exercisesheets.sty b/exercisesheets.sty
index 6616f9a..9c8c502 100644
--- a/exercisesheets.sty
+++ b/exercisesheets.sty
@@ -18,8 +18,8 @@
 %\NeedsTeXFormat{LaTeX2e}[1994/12/01]
 
 % don't forget to update the version and date in exercisesheets.tex
-\def\exsh@version{0.10+git}
-\def\exsh@date{2022/01/12}
+\def\exsh@version{0.11}
+\def\exsh@date{2022/02/11}
 
 \ProvidesPackage{exercisesheets}[\exsh@date\space\exsh@version\space Typesetting of exercise sheets]
 \message{`Typesetting of exercise sheets' \exsh@version\space <\exsh@date>}
@@ -43,6 +43,9 @@
 \RequirePackage{currfile}
 \RequirePackage{catchfile}
 
+%we need getrefnumber
+\RequirePackage{refcount}
+
 % configuration keys
 
 \newif\ifexsh@beamer 
@@ -877,8 +880,9 @@
     {\csname the#1\endcsname\autodot\enskip}}%
 }{}
 
-%Do nout use \let here as \label may change before its use
+%Do not use \let here as \label may change before its use
 \def\exsh@autolabel{\label}
+\def\inexlabel{\label}
 
 \newcounter{exsh@pts@cur}
 \newcounter{exsh@ptsbonus@cur}
@@ -1088,6 +1092,7 @@
   %auto labelling is still allowed, but other labels are forbidden
   %here we may use \let as the definition is close to its use
   \let\exsh@autolabel\label
+  \let\inexlabel\label
   \def\label##1{%
     \PackageError{exercisesheets}{\string\label{##1}\space
     inside \string\includeexercise*}{}%
@@ -1153,9 +1158,23 @@
   \labelformat{section}{\pgfkeysvalueof{/exsh/strings/exercise}~\arabic{section}}
 }
 
+
+\let\exsh@subexn\getrefnumber
+
 \ifexsh@patchenumerate
   \AfterPackage*{varioref}{
     \labelformat{enumi}{\arabic{section}.\alph{enumi}}
+    \def\exsh@afterdot#1.#2{#2}%x.y -> y
+    \def\exsh@subexn#1{%
+      \if\getrefnumber{#1}0%
+        0%
+      \else%x.y->y, then inverse \@alph
+        \the\numexpr(\expandafter\expandafter\expandafter%
+        \expandafter\expandafter\expandafter%
+        \expandafter`\expandafter\expandafter\expandafter%
+        \exsh@afterdot\getrefnumber{#1}-`a+1)\relax%
+      \fi%
+    }
   }
   \AfterPackage*{paralist}{
     \setdefaultenum{(a)}{(1)}{i.}{A.}
@@ -1182,6 +1201,29 @@
   }%
 \fi
 
+\newcommand{\subexnref}[1]{\exsh@subexn{#1}}
+\newcommand{\subexlref}[1]{(\@alph{\exsh@subexn{#1}})}
+
+%for now this is not part of the public interface
+\exshset{subtask counter/.initial={enumi}}
+\exshset{subtask environment/.initial={enumerate}}
+\exshset{subtask item/.initial={item}}
+\edef\exsh@subtaskctr{\pgfkeysvalueof{/exsh/subtask counter}}
+\def\exsh@subtaskenv{\pgfkeysvalueof{/exsh/subtask environment}}
+\def\exsh@subtaskitm{\pgfkeysvalueof{/exsh/subtask item}}
+
+%define subex as an alias for enumi
+\expandafter\let\expandafter\c@subex%
+  \csname c@\exsh@subtaskctr\endcsname
+\expandafter\let\expandafter\p@subex%
+  \csname p@\exsh@subtaskctr\endcsname
+\expandafter\let\expandafter\thesubex%
+  \csname the\exsh@subtaskctr\endcsname
+\expandafter\let\expandafter\theHsubex%
+  \csname theH\exsh@subtaskctr\endcsname
+\expandafter\let\expandafter\cl@subex%
+  \csname cl@\exsh@subtaskctr\endcsname
+
 % reset equation numbering for each exercise
 \@addtoreset{equation}{section}
 
@@ -1197,25 +1239,6 @@
   \ignorespaces
 }{}
 
-%we ignore everything before the frist item
-%and process everything afterwards
-\long\def\exsh@processsubtasks#1\item#2\item{%
-\ifstrequal{#2}{}{}{%
-\item #2%
-\csgdef{exsh@restatetask\arabic{enumi}}{#2}%
-\exsh@processsubtasks\item%new "frist" \item to ignore
-}%no whitespace here is crucial for end detecttion
-}
-
-\long\def\exsh@collectedsubtasks#1{
-\begin{enumerate}
-\exsh@processsubtasks#1\item\item
-\end{enumerate}%
-}
-
-\def\exsh@subtaskenv{enumerate}
-\def\exsh@subtaskitm{item}
-\def\exsh@subtaskctr{enumi}
 \newenvironment{subtasks}[1][]{%
   \pgfkeys{exsh,#1}%
   \begin{\exsh@subtaskenv}
@@ -1308,7 +1331,7 @@
     \pgfkeysvalueof{/exsh/solution title font}%
       \pgfkeysvalueof{/exsh/strings/solution} %
       (\pgfkeysvalueof{/exsh/strings/exercise} \arabic{section}%
-        \ifnum\@enumdepth>0\alph{enumi}\fi)%
+        \ifnum\@enumdepth>0\alph{subex}\fi)%
     \end{alertblock}
   }{
     \begin{beamercolorbox}[rounded=true,wd={#1}]%
@@ -1316,7 +1339,7 @@
       \pgfkeysvalueof{/exsh/solution title font}%
       \pgfkeysvalueof{/exsh/strings/solution} %
       (\pgfkeysvalueof{/exsh/strings/exercise} \arabic{section}%
-        \ifnum\@enumdepth>0\alph{enumi}\fi)%
+        \ifnum\@enumdepth>0\alph{subex}\fi)%
     \end{beamercolorbox}
   }
 }
@@ -1367,7 +1390,7 @@
 %     \pgfkeysvalueof{/exsh/solution title font}%
 %     \pgfkeysvalueof{/exsh/strings/solution} %
 %     (\pgfkeysvalueof{/exsh/strings/exercise} \arabic{section}%
-%     \alph{enumi})%
+%     \alph{subex})%
 %   \endblock
   \ifbool{exsh@framed}{\exsh@defersolutiontitletrue}{}
   \ifbool{exsh@defersolutiontitle}{}{%