exsheets/tasks 0.7a (22jan13)

git-svn-id: svn://tug.org/texlive/trunk@28907 c570f23f-e606-0410-a88d-b1316a301751

4 files changed, 585 insertions, 456 deletions

diff --git a/Master/texmf-dist/tex/latex/exsheets/exsheets.sty b/Master/texmf-dist/tex/latex/exsheets/exsheets.sty
index 7c939d9de03..6ac2e4dddc0 100644
--- a/Master/texmf-dist/tex/latex/exsheets/exsheets.sty
+++ b/Master/texmf-dist/tex/latex/exsheets/exsheets.sty
@@ -31,8 +31,8 @@
 % If you have any ideas, questions, suggestions or bugs to report, please
 % feel free to contact me.
 % ----------------------------------------------------------------------------
-\def\exsheets@date{2013/01/06}
-\def\exsheets@version{0.6b}
+\def\exsheets@date{2013/01/21}
+\def\exsheets@version{0.7a}
 
 \RequirePackage { expl3 , xparse }
 \ProvidesExplPackage
@@ -48,6 +48,8 @@
 \tl_new:N    \l__exsheets_tmpc_tl
 \int_new:N   \l__exsheets_tmpa_int
 \int_new:N   \l__exsheets_tmpb_int
+\int_new:N   \l__exsheets_tmpc_int
+\int_new:N   \l__exsheets_tmpd_int
 \dim_new:N   \l__exsheets_tmpa_dim
 \seq_new:N   \l__exsheets_tmpa_seq
 \fp_new:N    \l__exsheets_tmpa_fp
@@ -119,7 +121,7 @@
 
 % ----------------------------------------------------------------------------
 \RequirePackage
-  { xtemplate , l3sort , l3keys2e , xcolor , etoolbox , environ , lcg , silence }
+  { xtemplate , l3sort , l3keys2e , xcolor , etoolbox , environ , pgfcore }
 
 % ----------------------------------------------------------------------------
 % color:
@@ -161,6 +163,7 @@
 \bool_new:N \l__exsheets_solutions_by_ref_bool
 \bool_new:N \l__exsheets_questions_totoc_bool
 \bool_new:N \l__exsheets_solutions_totoc_bool
+\bool_new:N \l__exsheets_auto_label_bool
 
 \tl_new:N   \l__exsheets_heading_instance_tl
 \tl_set:Nn  \l__exsheets_heading_instance_tl { block }
@@ -206,7 +209,8 @@
       \tl_set:Nn \l__exsheets_questions_toclevel_tl { #1 }
       \tl_set:Nn \l__exsheets_solutions_toclevel_tl { #1 } ,
     questions-toc-level       .tl_set:N   = \l__exsheets_questions_toclevel_tl ,
-    solutions-toc-level       .tl_set:N   = \l__exsheets_solutions_toclevel_tl
+    solutions-toc-level       .tl_set:N   = \l__exsheets_solutions_toclevel_tl ,
+    auto-label                .bool_set:N = \l__exsheets_auto_label_bool
   }
 \keys_set:nn { exsheets} { counter-format = qu. }
 
@@ -939,6 +943,7 @@
 \tl_new:N   \l__exsheets_questions_meta_tl
 \tl_new:N   \g__exsheets_questions_current_id_tl
 \tl_new:N   \l__exsheets_title_tl
+\tl_new:N   \l__exsheets_questions_label_tl
 
 \bool_new:N \l__exsheets_points_not_given_bool
 
@@ -966,35 +971,63 @@
     % Optionen:
     \IfNoValueF { #1 } { \keys_set:nn { exsheets / question } { #1 } }
     % ID:
-    \int_gincr:N \g__exsheets_questions_id_int
-    \tl_if_blank:VTF \l__exsheets_questions_id_tl
+    \bool_if:nT
+      { 
+        (\l__exsheets_questions_deactivate_bool && \l__exsheets_select_questions_bool)
+          ||
+        !\l__exsheets_select_questions_bool
+      }
       {
-        \prop_gput:NVV \g__exsheets_questions_id_prop
-          \g__exsheets_questions_id_int
-          \g__exsheets_questions_id_int
-        \bool_if:NT \l__exsheets_questions_use_bool
+        \int_gincr:N \g__exsheets_questions_id_int
+        \tl_if_blank:VTF \l__exsheets_questions_id_tl
           {
-            \prop_gput:NVV \g__exsheets_questions_used_prop
+            \prop_gput:NVV \g__exsheets_questions_id_prop
               \g__exsheets_questions_id_int
               \g__exsheets_questions_id_int
-            \int_gincr:N \g__exsheets_questions_used_int
+            \bool_if:NT \l__exsheets_questions_use_bool
+              {
+                \prop_gput:NVV \g__exsheets_questions_used_prop
+                  \g__exsheets_questions_id_int
+                  \g__exsheets_questions_id_int
+                \int_gincr:N \g__exsheets_questions_used_int
+              }
+            \tl_gset:Nx \g__exsheets_questions_current_id_tl
+              { \int_use:N \g__exsheets_questions_id_int }
           }
-        \tl_gset:Nx \g__exsheets_questions_current_id_tl
-          { \int_use:N \g__exsheets_questions_id_int }
-      }
-      {
-        \prop_gput:NVV \g__exsheets_questions_id_prop
-          \l__exsheets_questions_id_tl
-          \g__exsheets_questions_id_int
-        \bool_if:NT \l__exsheets_questions_use_bool
           {
-            \prop_gput:NVV \g__exsheets_questions_used_prop
+            \prop_gput:NVV \g__exsheets_questions_id_prop
               \l__exsheets_questions_id_tl
               \g__exsheets_questions_id_int
-            \int_gincr:N \g__exsheets_questions_used_int
+            \bool_if:NT \l__exsheets_questions_use_bool
+              {
+                \prop_gput:NVV \g__exsheets_questions_used_prop
+                  \l__exsheets_questions_id_tl
+                  \g__exsheets_questions_id_int
+                \int_gincr:N \g__exsheets_questions_used_int
+              }
+            \tl_gset:Nx \g__exsheets_questions_current_id_tl
+              { \tl_use:N \l__exsheets_questions_id_tl }
+          }
+        \tl_if_blank:VTF \l__exsheets_questions_label_tl
+          {
+            \bool_if:NT \l__exsheets_auto_label_bool
+              {
+                \exp_args:Nx \label { qu : \g__exsheets_questions_current_id_tl }
+                \exp_args:Nx \SetQuestionProperties
+                  {
+                    ref = \exp_not:N \ref { qu : \g__exsheets_questions_current_id_tl } ,
+                    pageref = \exp_not:N \pageref { qu : \g__exsheets_questions_current_id_tl }
+                  }
+              }
+          }
+          {
+            \exp_args:Nx \label { \l__exsheets_questions_label_tl }
+            \exp_args:Nx \SetQuestionProperties
+              {
+                ref = \exp_not:N \ref { \l__exsheets_questions_label_tl } ,
+                pageref = \exp_not:N \pageref { \l__exsheets_questions_label_tl }
+              }
           }
-        \tl_gset:Nx \g__exsheets_questions_current_id_tl
-          { \tl_use:N \l__exsheets_questions_id_tl }
       }
     % Punktevergabe:
     \IfNoValueTF { #2 }
@@ -1062,6 +1095,7 @@
           }
         \bool_if:NT \l__exsheets_questions_print_bool
           {
+%             \exsheets_questions_debug:
             \bool_if:NTF \l__exsheets_exam_bool
               { \tl_set_eq:NN \l__exsheets_title_tl \l__exsheets_questions_name_tl }
               { \tl_set_eq:NN \l__exsheets_title_tl \l__exsheets_exsheets_name_tl }
@@ -1217,6 +1251,7 @@
     print           .bool_set:N  = \l__exsheets_questions_print_bool ,
     print           .default:n   = true ,
     ID              .tl_set:N    = \l__exsheets_questions_id_tl ,
+    label           .tl_set:N    = \l__exsheets_questions_label_tl ,
     class           .code:n      =
       \bool_set_true:N \l__exsheets_questions_class_bool
       \tl_set:Nn \l__exsheets_questions_class_tl { #1 } ,
@@ -1251,6 +1286,11 @@
 \@onlypreamble\DeclareQuestionProperty
 
 \DeclareQuestionProperty{points}
+\bool_if:NT \l__exsheets_auto_label_bool
+  {
+    \DeclareQuestionProperty{ref}
+    \DeclareQuestionProperty{pageref}
+  }
 
 \NewDocumentCommand \SetQuestionProperties { m }
   { \exsheets_set_question_properties:n { #1 } }
@@ -1345,11 +1385,8 @@
 \clist_new:N     \l__exsheets_include_id_clist
 \int_new:N       \l__exsheets_include_random_int
 \int_zero:N      \l__exsheets_include_random_int
-\tl_new:N        \l__exsheets_random_seed_tl
-\tl_set:Nn       \l__exsheets_random_seed_tl { -1 }
-\newcounter      {exsheets@include@random}
 
-\cs_new:Npn \file_input_if_exist:n #1
+\cs_new:Npn \exsheets_file_input_if_exist:n #1
   { \file_if_exist:nT { #1 } { \file_input:n { #1 } } }
 
 \cs_if_exist:NF \prop_length:N
@@ -1379,16 +1416,16 @@
 
 \cs_new:Npn \exsheets_include_questions:n #1
   {
+    \bool_set_true:N \l__exsheets_select_questions_bool
     \seq_set_split:Nnn \l__exsheets_tmpa_seq { , } { #1 }
     \seq_map_inline:Nn \l__exsheets_tmpa_seq
       {
         \bool_set_true:N \l__exsheets_questions_deactivate_bool
-        \file_input_if_exist:n { ##1 }
+        \int_set_eq:NN \l__exsheets_tmpc_int \g__exsheets_questions_id_int
+        \exsheets_file_input_if_exist:n { ##1 }
         \prop_length:NN
           \g__exsheets_selected_questions_prop
           \l__exsheets_tmpa_int
-        \int_gsub:Nn \g__exsheets_questions_id_int
-          { \l__exsheets_tmpa_int }
         \bool_if:NT \l__exsheets_questions_debug_bool
           {
             \colorbox { exsheetsdebugcolor }
@@ -1400,18 +1437,22 @@
               \exsheets_par:
           }
         \bool_set_false:N \l__exsheets_questions_deactivate_bool
+        \int_set_eq:NN \l__exsheets_tmpd_int \g__exsheets_questions_id_int
+        \int_gset_eq:NN \g__exsheets_questions_id_int \l__exsheets_tmpc_int
         \__exsheets_select_question_random:n { ##1 }
-        \file_input_if_exist:n { ##1 }
+        \exsheets_file_input_if_exist:n { ##1 }
+        \int_gset_eq:NN \g__exsheets_questions_id_int \l__exsheets_tmpd_int
         \prop_gclear:N \g__exsheets_selected_questions_prop
         \clist_clear:N \l__exsheets_include_id_clist
+        \int_gzero:N \g__exsheets_selection_number_int
       }
+    \bool_set_false:N \l__exsheets_select_questions_bool
   }
 
 % options:
 %  - IDs=<list of IDs>
 %  - all=true|false    % default when no option is given
 %  - random=<num>
-%  - seed=<num>        % set the seed for the random selection
 \keys_define:nn { exsheets / include }
   {
     all    .bool_set:N = \l__exsheets_include_all_bool ,
@@ -1422,20 +1463,34 @@
     random .code:n     =
       \bool_set_false:N \l__exsheets_include_all_bool
       \bool_set_true:N  \l__exsheets_include_random_bool
-      \int_set:Nn \l__exsheets_include_random_int { #1 } ,
-    seed   .tl_set:N   = \l__exsheets_random_seed_tl
+      \int_set:Nn \l__exsheets_include_random_int { #1 }
   }
 
+\int_new:N \g__exsheets_selection_number_int
+
 \cs_new:Npn \__exsheets_select_question:n #1
   {
-    \bool_if:NTF \l__exsheets_questions_deactivate_bool
+    \bool_if:NT \l__exsheets_select_questions_bool
       {
-        \prop_gput:Nnn \g__exsheets_selected_questions_prop
-          { #1 } { \__exsheets_dummy: }
-      }
-      {
-        \bool_if:NF \l__exsheets_include_all_bool
-          { \__exsheets_select_question_by_id:n { #1 } }
+        \bool_if:NTF \l__exsheets_questions_deactivate_bool
+          {
+            \bool_if:NT \l__exsheets_questions_use_bool
+              {
+                \int_gincr:N \g__exsheets_selection_number_int
+                \exp_args:NNx
+                \prop_gput:Nnn \g__exsheets_selected_questions_prop
+                  { \int_use:N \g__exsheets_selection_number_int } { #1 }
+              }
+          }
+          {
+            \int_gincr:N \g__exsheets_questions_id_int
+            \exp_args:NNx
+            \prop_get:NnN \g__exsheets_questions_id_prop
+              {  \int_use:N \g__exsheets_questions_id_int }
+              \l_tmpa_tl
+            \bool_if:NF \l__exsheets_include_all_bool
+              { \__exsheets_select_question_by_id:V \l_tmpa_tl }
+          }
       }
   }
 \cs_generate_variant:Nn \__exsheets_select_question:n { V }
@@ -1448,6 +1503,7 @@
       { \bool_gset_true:N  \g__exsheets_questions_use_bool }
       { \bool_gset_false:N \g__exsheets_questions_use_bool }
   }
+\cs_generate_variant:Nn \__exsheets_select_question_by_id:n { V }
 
 % TODO: don't select questions whose topics or classes aren't chosen
 \cs_new:Npn \__exsheets_select_question_random:n #1
@@ -1464,44 +1520,22 @@
             \bool_set_true:N \l__exsheets_include_all_bool
           }
           {
-            \group_begin:
-              \WarningsOff[lcg]
-              \tl_set:Nx \l__exsheets_tmpa_tl { \int_use:N \l__exsheets_tmpa_int }
-              \reinitrand
-                [
-                  first   = 1 ,
-                  last    = \l__exsheets_tmpa_tl ,
-                  counter = exsheets@include@random ,
-                  seed    = \l__exsheets_random_seed_tl ,
-                  quiet   = y
-                ]
-              \int_zero:N \l__exsheets_tmpa_int
-              \int_do_while:nNnn \l__exsheets_tmpa_int < \l__exsheets_include_random_int
-                {
-                  \rand
-                  \int_zero:N \l__exsheets_tmpb_int
-                  \prop_map_inline:Nn \g__exsheets_selected_questions_prop
-                    {
-                      \int_incr:N \l__exsheets_tmpb_int
-                      \int_compare:nT
-                        { \l__exsheets_tmpb_int = \value{exsheets@include@random} }
-                        {
-                          \tl_set_rescan:Nnn \l__exsheets_tmpa_tl {} { ##1 }
-                          \clist_if_in:NVTF \l__exsheets_include_id_clist \l__exsheets_tmpa_tl
-                            { \int_decr:N \l__exsheets_tmpb_int }
-                            {
-                              \clist_gput_right:NV \l__exsheets_include_id_clist
-                                \l__exsheets_tmpa_tl
-                              \prop_map_break:
-                            }
-                        }
-                    }
-                    \clist_remove_duplicates:N \l__exsheets_include_id_clist
-                    \int_set:Nn \l__exsheets_tmpa_int
-                      { \clist_count:N \l__exsheets_include_id_clist }
-                }
-              \WarningsOn[lcg]
-            \group_end:
+            \int_zero:N \l__exsheets_tmpb_int
+            \int_do_while:nn { \l__exsheets_tmpb_int < \l__exsheets_include_random_int }
+              {
+                \pgfmathparse { random(\int_use:N \l__exsheets_tmpa_int) }
+                \tl_set_eq:NN \l__exsheets_tmpa_tl \pgfmathresult
+                \prop_get:NVN \g__exsheets_selected_questions_prop
+                  \l__exsheets_tmpa_tl
+                  \l__exsheets_tmpb_tl
+                \clist_if_in:NVF \l__exsheets_include_id_clist \l__exsheets_tmpb_tl
+                  {
+                    \clist_put_right:NV
+                      \l__exsheets_include_id_clist
+                      \l__exsheets_tmpb_tl
+                    \int_incr:N \l__exsheets_tmpb_int
+                  }
+              }
           }
       }
   }
@@ -2040,12 +2074,11 @@
 
 % ----------------------------------------------------------------------------
 % the `tasks' list
-\input { exsheets_tasks.def }
-\bool_if:NT \l__exsheets_load_tasks_bool
-  {
-    \RequirePackage { amssymb }
-    \input { exsheets_tasks.cfg }
-  }
+\bool_if:NTF \l__exsheets_load_tasks_bool
+  { \RequirePackage [ more ] { tasks } }
+  { \RequirePackage { tasks } }
+\AddCounterPattern* [ tasks ] { question } { qu }
+\ReadCounterFrom [ tasks ] { question } \l__exsheets_counter_qu_int
 
 % ----------------------------------------------------------------------------
 % the \blank{<words>} command
@@ -2365,9 +2398,17 @@ HISTORY:
 2012/12/23 v0.6a       - bug fix: labels and items of {tasks} weren't joined at
                          their baselines
 2013/01/06 v0.6b       - bug fix: ID counting fixed in \includequestions
+2013/01/19 v0.7        - extracted `tasks' environment into standalone package;
+                         this also lead to a slightly new syntax and a few new
+                         options for it
+                       - changed internals for random selection of questions:
+                         uses `pgf' instead of `lcg' and seems to be more reliable
+                         than before
+2013/01/21 v0.7a       - added option `auto-label' and questions key `label',
+                         also added question properties `ref' and `pageref'
+
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % TODO:
 - points/decimal-marker, points/frac (?), points/format (?,im interface)
-- bug in {tasks} in {solution}: label werden nicht richtig upgedatet!
-- bug: counter-format=se.qu und \begin{solution}[print]
\ No newline at end of file
+- rewrite random selection
diff --git a/Master/texmf-dist/tex/latex/exsheets/exsheets_tasks.def b/Master/texmf-dist/tex/latex/exsheets/exsheets_tasks.def
deleted file mode 100644
index facab8e6553..00000000000
--- a/Master/texmf-dist/tex/latex/exsheets/exsheets_tasks.def
+++ /dev/null
@@ -1,356 +0,0 @@
-% --------------------------------------------------------------------------
-% the EXSHEETS package
-% 
-%   Yet another package for the creation of exercise sheets
-% 
-% --------------------------------------------------------------------------
-% Clemens Niederberger
-% Web:    https://bitbucket.org/cgnieder/exsheets/
-% E-Mail: contact@mychemistry.eu
-% --------------------------------------------------------------------------
-% Copyright 2011-2013 Clemens Niederberger
-% 
-% This work may be distributed and/or modified under the
-% conditions of the LaTeX Project Public License, either version 1.3
-% of this license or (at your option) any later version.
-% The latest version of this license is in
-%   http://www.latex-project.org/lppl.txt
-% and version 1.3 or later is part of all distributions of LaTeX
-% version 2005/12/01 or later.
-% 
-% This work has the LPPL maintenance status `maintained'.
-% 
-% The Current Maintainer of this work is Clemens Niederberger.
-% --------------------------------------------------------------------------
-% The exsheets package consists of the files
-%  - exsheets.sty, exsheets_headings.def, exsheets_headings.cfg,
-%    exsheets_tasks.def, exsheets_tasks.cfg, exsheets_configurations.cfg,
-%  - exsheets_en.tex, exsheets_en.pdf,
-%  - README
-% --------------------------------------------------------------------------
-% If you have any ideas, questions, suggestions or bugs to report, please
-% feel free to contact me.
-% --------------------------------------------------------------------------
-% TASKS: LIST-LIKE ENVIRONMENT
-\ProvidesFile{exsheets_tasks.def}
-  [\exsheets@date\space v\exsheets@version\space ExSheets tasks object]
-
-\RequirePackage { epic }
-
-% variables:
-\seq_new:N    \l__exsheets_tasks_seq
-\int_new:N    \l__exsheets_tasks_depth_int
-\int_new:N    \g__exsheets_tasks_int
-\int_new:N    \l__exsheets_tasks_total_items_int
-\int_new:N    \l__exsheets_tasks_columns_int
-\int_new:N    \l__exsheets_tasks_rows_int
-\bool_new:N   \l__exsheets_tasks_enumerate_bool
-\bool_new:N   \l__exsheets_tasks_resume_bool
-\tl_new:N     \l__exsheets_tasks_instance_tl
-\tl_new:N     \l__exsheets_tasks_label_tl
-\tl_new:N     \l__exsheets_tasks_label_pattern_tl
-\tl_new:N     \l__exsheets_tasks_custom_label_format_tl
-\dim_new:N    \l__exsheets_tasks_item_indent_dim
-\dim_new:N    \l__exsheets_tasks_item_width_dim
-\dim_new:N    \l__exsheets_tasks_label_width_dim
-\dim_new:N    \l__exsheets_tasks_default_label_width_dim
-\skip_new:N   \l__exsheets_tasks_after_item_skip
-\skip_new:N   \l__exsheets_tasks_before_list_skip
-\skip_new:N   \l__exsheets_tasks_after_list_skip
-
-\NewCounterPattern* [ exsheets ] { task } { tsk }
-\ReadCounterFrom [ exsheets ] { task } \g__exsheets_tasks_int
-
-% scratch coffins:
-\cs_if_exist:NF \l__exsheets_tmpa_coffin { \coffin_new:N \l__exsheets_tmpa_coffin }
-\cs_if_exist:NF \l__exsheets_tmpb_coffin { \coffin_new:N \l__exsheets_tmpb_coffin }
-\cs_if_exist:NF \l__exsheets_tmpc_coffin { \coffin_new:N \l__exsheets_tmpc_coffin }
-
-% collect the tasks:
-\cs_new:Npn \__exsheets_collect_tasks:nw #1#2 \end #3
-  {
-    \tl_put_right:Nn \l__exsheets_tasks_body_tl { #1 }
-    \end { #3 }
-    \tl_if_eq:nnF { #1 } { #3 }
-      { \__exsheets_collect_tasks:nw { #1 } }
-  }
-
-%  #1: instance
-%  #2: number of columns
-%  #3: item separator
-%  #4: environment body
-\cs_new:Npn \__exsheets_tasks:nnnn #1#2#3#4
-  {
-    \seq_set_split:Nnn \l__exsheets_tasks_seq { #3 } { #4 }
-    % remove the first (empty) item:
-    \seq_pop_left:NN \l__exsheets_tasks_seq \l__exsheets_tmpa_tl
-    \tl_if_blank:VF \l__exsheets_tmpa_tl
-      { \tl_show:N \l__exsheets_tmpa_tl \@noitemerr }
-    \int_set:Nn \l__exsheets_tasks_total_items_int
-      { \seq_length:N \l__exsheets_tasks_seq }
-    \UseInstance { exsheets-tasks } { #1 }
-      { \l__exsheets_tasks_total_items_int }
-      { #2 }
-      { \l__exsheets_tasks_custom_label_format_tl }
-    % just to be sure:
-    \seq_clear:N \l__exsheets_tasks_seq
-  }
-\cs_generate_variant:Nn \__exsheets_tasks:nnnn { VnnV }
-
-\cs_new:Npn \__exsheets_task:nnw #1#2[#3,#4][#5,#6](#7,#8)
-  {
-    \dim_set:Nn \l__exsheets_tasks_item_width_dim
-      {
-        \linewidth / \l__exsheets_tasks_columns_int -
-        \l__exsheets_tasks_depth_int \l__exsheets_tasks_item_indent_dim
-      }
-    \int_incr:N \l__exsheets_tmpa_int
-    \__exsheets_tasks_set_rows_num:NN
-      \l__exsheets_tasks_total_items_int
-      \l__exsheets_tasks_columns_int
-    \int_compare:nT { \l__exsheets_tmpa_int > \l__exsheets_tasks_columns_int }
-      { \int_set:Nn \l__exsheets_tmpa_int { 1 } }
-    % the item:
-    \hcoffin_set:Nn \l__exsheets_tmpa_coffin
-      {
-        \vcoffin_set:Nnn \l__exsheets_tmpc_coffin
-          { \l__exsheets_tasks_item_width_dim }
-          { \__exsheets_tasks_setup: #2 }
-        \coffin_typeset:Nnnnn \l__exsheets_tmpc_coffin
-          { l } { T } { 0pt } { 0pt }
-      }
-    % the label:
-    \hcoffin_set:Nn \l__exsheets_tmpb_coffin { \strut #1 }
-    \coffin_attach:NnnNnnnn
-      \l__exsheets_tmpa_coffin { l } { T }
-      \l__exsheets_tmpb_coffin { l } { T } { -\l__exsheets_tasks_label_width_dim } { 0pt }
-    % typeset label & item:
-    % need this when a new row starts:
-    \int_compare:nT { \l__exsheets_tmpa_int = 1 }
-      { \skip_vertical:N \c_zero_skip }
-    \skip_horizontal:N \l__exsheets_tasks_item_indent_dim
-    \coffin_typeset:Nnnnn \l__exsheets_tmpa_coffin { l } { T } { 0pt } { 0pt }
-    % need this before a new row starts:
-    \int_compare:nT { \l__exsheets_tmpa_int = \l__exsheets_tasks_columns_int }
-      { \skip_vertical:N \l__exsheets_tasks_after_item_skip }
-    \coffin_clear:N \l__exsheets_tmpa_coffin
-    \coffin_clear:N \l__exsheets_tmpb_coffin
-    \coffin_clear:N \l__exsheets_tmpc_coffin
-  }
-\cs_generate_variant:Nn \__exsheets_task:nnw { VV }
-
-\cs_new:Npn \__exsheets_tasks_setup:
-  {
-    \dim_set:Nn \parskip { 0pt }
-    \skip_set:Nn \parfillskip { 0pt plus 1fil }
-    \dim_set_eq:NN \parskip \parsep
-    \dim_set_eq:NN \parindent \listparindent
-    \strut
-  }
-
-\cs_new:Npn \__exsheets_tasks_set_rows_num:NN #1#2
-  {
-    \int_set:Nn \l__exsheets_tasks_rows_int { \int_div_truncate:nn { #1 } { #2 } }
-    \int_compare:nNnT { \int_mod:nn { #1 } { #2 } } > { 0 }
-      { \int_incr:N \l__exsheets_tasks_rows_int }
-  }
-
-% the `exsheets-tasks' object:
-%   #1: number of items
-%   #2: number of columns
-%   #3: label-format
-\DeclareObjectType { exsheets-tasks } { 3 }
-% the `default' template interface:
-\DeclareTemplateInterface { exsheets-tasks } { default } { 3 }
-  {
-    enumerate       : boolean   = true    ,
-    label           : tokenlist           ,
-    indent          : length    = 2.5em   ,
-    label-format    : tokenlist = tsk[a]) ,
-    label-width     : length    = 3ex     ,
-    after-item-skip : skip      = 1ex plus 1ex minus 1ex
-  }
-% the `default' template code:
-\DeclareTemplateCode { exsheets-tasks } { default } { 3 }
-  {
-    enumerate       = \l__exsheets_tasks_enumerate_bool          ,
-    label           = \l__exsheets_tasks_label_tl                ,
-    indent          = \l__exsheets_tasks_item_indent_dim         ,
-    label-format    = \l__exsheets_tasks_label_pattern_tl         ,
-    label-width     = \l__exsheets_tasks_default_label_width_dim ,
-    after-item-skip = \l__exsheets_tasks_after_item_skip
-  }
-  {
-    \AssignTemplateKeys
-    \dim_compare:nT { \l__exsheets_tasks_label_width_dim = 0pt }
-      {
-        \dim_set_eq:NN
-          \l__exsheets_tasks_label_width_dim
-          \l__exsheets_tasks_default_label_width_dim
-      }
-    % need this for enumerate list:
-    \bool_if:nT { !\l__exsheets_tasks_resume_bool && \l__exsheets_tasks_enumerate_bool }
-      { \int_gzero:N \g__exsheets_tasks_int }
-    \int_set:Nn \l__exsheets_tasks_columns_int { #2 }
-    % set all the items in their own coffins and join with the ground:
-    \int_zero:N \l__exsheets_tmpa_int
-    \tl_if_blank:VF \l__exsheets_tasks_custom_label_format_tl
-      {
-        \tl_set_eq:NN
-          \l__exsheets_tasks_label_pattern_tl
-          \l__exsheets_tasks_custom_label_format_tl
-      }
-    \seq_map_inline:Nn \l__exsheets_tasks_seq
-      {
-        \__exsheets_read_item:w ##1 \q_stop
-        \bool_if:NTF \l__exsheets_tasks_enumerate_bool
-          {
-            \int_gincr:N \g__exsheets_tasks_int
-            \tl_if_blank:VT \l__exsheets_tasks_label_tl
-              {
-                \tl_set:Nn \l__exsheets_tasks_label_tl
-                  {
-                    \ReadCounterPatternFrom [ exsheets ]
-                      \l__exsheets_tasks_label_pattern_tl
-                  }
-              }
-          }
-          {
-            \tl_if_blank:VT \l__exsheets_tasks_label_tl
-              { \tl_set_eq:NN \l__exsheets_tasks_label_tl \labelitemi }
-          }
-        \tl_if_blank:VTF \l__exsheets_tasks_tmp_label_tl
-          {
-            \__exsheets_task:VVw
-              \l__exsheets_tasks_label_tl
-              \l__exsheets_tasks_item_tl
-              [ l , b ] [ l , t ] ( 0pt , 0pt )
-          }
-          {
-            \__exsheets_task:VVw
-              \l__exsheets_tasks_tmp_label_tl
-              \l__exsheets_tasks_item_tl
-              [ l , b ] [ l , t ] ( 0pt , 0pt )
-            \tl_clear:N \l__exsheets_tasks_tmp_label_tl
-          }
-      }
-  }
-
-\tl_new:N \task
-\tl_new:N \l__exsheets_tasks_item_tl
-\tl_new:N \l__exsheets_tasks_tmp_label_tl
-
-\cs_new:Npn \__exsheets_read_item:w
-  {
-    \peek_meaning:NTF [
-      { \__exsheets_read_item_aux:w }
-      { \__exsheets_read_item_aux:w[] }
-  }
-
-\cs_new:Npn \__exsheets_read_item_aux:w [#1]#2 \q_stop
-  {
-    \tl_if_blank:nF { #1 }
-      { \tl_set:Nn \l__exsheets_tasks_tmp_label_tl { #1 } }
-    \tl_set:Nn \l__exsheets_tasks_item_tl { \ignorespaces #2 }
-  }
-
-% choice box:
-\bool_new:N \l__exsheets_choice_checked_bool
-\dim_new:N  \l__exsheets_choice_width_dim
-\dim_set:Nn \l__exsheets_choice_width_dim { 1.25ex }
-\dim_new:N  \l__exsheets_choice_linewidth_dim
-\dim_set:Nn \l__exsheets_choice_linewidth_dim { .3pt }
-\dim_new:N  \l__exsheets_choice_checkwidth_dim
-\dim_set:Nn \l__exsheets_choice_checkwidth_dim { .5pt }
-\dim_new:N  \l__exsheets_choice_raise_dim
-\dim_set:Nn \l__exsheets_choice_raise_dim { .1ex }
-
-\cs_new:Npn \exsheets_choice:
-  {
-    \leavevmode
-    \bool_set_false:N \l__exsheets_choice_checked_bool
-    \box_move_up:nn
-      { \l__exsheets_choice_raise_dim }
-      { \hbox:n { \__exsheets_choice: } }
-  }
-
-\cs_new:Npn \exsheets_choice_checked:
-  {
-    \leavevmode
-    \bool_set_true:N \l__exsheets_choice_checked_bool
-    \box_move_up:nn
-      { \l__exsheets_choice_raise_dim }
-      { \hbox:n { \__exsheets_choice: } }
-  }
-
-\cs_new:Npn \__exsheets_choice:
-  {%
-    \dim_set:Nn \unitlength { .1\l__exsheets_choice_width_dim }
-    \begin{picture}(10,0)
-      \linethickness \l__exsheets_choice_linewidth_dim
-      \drawline(0,0)(0,10)(10,10)(10,0)(0,0)
-      \linethickness \l__exsheets_choice_checkwidth_dim
-      \bool_if:NT \l__exsheets_choice_checked_bool
-        {
-          \drawline(2,2)(8,8)
-          \drawline(2,8)(8,2)
-        }
-    \end{picture}%
-  }
-
-\providecommand* \choicebox { \exsheets_choice: }
-\providecommand* \checkedchoicebox { \exsheets_choice_checked: }
-
-% base instance:
-% ALPHABETIZE: a) b) c)
-\DeclareInstance { exsheets-tasks } { alphabetize } { default } { }
-
-\keys_define:nn { exsheets / tasks }
-  {
-    style       .tl_set:N   = \l__exsheets_tasks_instance_tl ,
-    label       .tl_set:N   = \l__exsheets_tasks_custom_label_format_tl ,
-    label-width .dim_set:N  = \l__exsheets_tasks_label_width_dim ,
-    before-skip .skip_set:N = \l__exsheets_tasks_before_list_skip ,
-    after-skip  .skip_set:N = \l__exsheets_tasks_after_list_skip ,
-    resume      .bool_set:N = \l__exsheets_tasks_resume_bool
-  }
-
-% the generic environment:
-\NewEnviron { __exsheets_tasks_env: } [ 3 ]
-  {
-    \keys_set:nn { exsheets / tasks } { #2 }
-    \tl_if_blank:VT \l__exsheets_tasks_instance_tl
-      { \keys_set:nn { exsheets / tasks } { style = alphabetize } }
-    \skip_vertical:N \l__exsheets_tasks_before_list_skip
-    \skip_vertical:N \c_zero_skip
-    \list {}
-      {
-        \dim_set:Nn \leftmargin { 0pt }
-        \dim_set:Nn \rightmargin { 0pt }
-      }
-    \item \scan_stop:
-    \int_incr:N \l__exsheets_tasks_depth_int
-    \__exsheets_tasks:VnnV \l__exsheets_tasks_instance_tl { #3 } { #1 } \BODY
-    \endlist
-    \skip_vertical:N \l__exsheets_tasks_after_list_skip
-  }
-
-% the user environment:
-\NewDocumentCommand \NewTasks { O{}mO{\task}D(){1} }
-  {
-    \NewDocumentEnvironment { #2 } { O{}G{#4} }
-      { \__exsheets_tasks_env: { #3 } { #1,##1 } { ##2 } }
-      { \end__exsheets_tasks_env: }
-  }
-
-\NewDocumentCommand \RenewTasks { O{}mO{\task}D(){1} }
-  {
-    \RenewDocumentEnvironment { #2 } { O{}G{#4} }
-      { \__exsheets_tasks_env: { #3 } { #1,##1 } { ##2 } }
-      { \end__exsheets_tasks_env: }
-  }
-
-\NewTasks { tasks }
-
-\tex_endinput:D
-% TODO: option für after-item-skip
\ No newline at end of file
diff --git a/Master/texmf-dist/tex/latex/exsheets/exsheets_tasks.cfg b/Master/texmf-dist/tex/latex/exsheets/tasks.cfg
index b99fdda993f..fb8923ef0d6 100644
--- a/Master/texmf-dist/tex/latex/exsheets/exsheets_tasks.cfg
+++ b/Master/texmf-dist/tex/latex/exsheets/tasks.cfg
@@ -1,7 +1,7 @@
 % --------------------------------------------------------------------------
-% the EXSHEETS package
+% the TASKS package
 % 
-%   Yet another package for the creation of exercise sheets
+%   Horizontal columned lists.
 % 
 % --------------------------------------------------------------------------
 % Clemens Niederberger
@@ -22,32 +22,31 @@
 % 
 % The Current Maintainer of this work is Clemens Niederberger.
 % --------------------------------------------------------------------------
-% The exsheets package consists of the files
-%  - exsheets.sty, exsheets_headings.def, exsheets_headings.cfg,
-%    exsheets_tasks.def, exsheets_tasks.cfg, exsheets_configurations.cfg,
-%  - exsheets_en.tex, exsheets_en.pdf,
-%  - README
+% The tasks package consists of the files
+%  - tasks.sty, tasks.cfg
 % --------------------------------------------------------------------------
 % If you have any ideas, questions, suggestions or bugs to report, please
 % feel free to contact me.
 % --------------------------------------------------------------------------
 % further instances for the `tasks' environment
-\ProvidesFile{exsheets_tasks.cfg}
-  [\exsheets@date\space v\exsheets@version\space ExSheets tasks instances]
+\ProvidesFile{tasks.cfg}
+  [\@tasks@date\space v\@tasks@version\space tasks instances]
+
+\cs_new:Npn \tasks_config_file_loaded: {}
 
 % ITEMIZE:
-\DeclareInstance { exsheets-tasks } { itemize } { default }
+\DeclareInstance { tasks } { itemize } { default }
   {
     enumerate    = false ,
     label-width  = 2.25ex
   }
 
 % ENUMERATE:
-\DeclareInstance { exsheets-tasks } { enumerate } { default }
+\DeclareInstance { tasks } { enumerate } { default }
   { label-format = tsk. }
 
 % MULTIPLECHOICE
-\DeclareInstance { exsheets-tasks } { multiplechoice } { default }
+\DeclareInstance { tasks } { multiplechoice } { default }
   {
     enumerate    = false       ,
     label        = \choicebox
diff --git a/Master/texmf-dist/tex/latex/exsheets/tasks.sty b/Master/texmf-dist/tex/latex/exsheets/tasks.sty
new file mode 100644
index 00000000000..88b613d7dbd
--- /dev/null
+++ b/Master/texmf-dist/tex/latex/exsheets/tasks.sty
@@ -0,0 +1,445 @@
+% --------------------------------------------------------------------------
+% the TASKS package
+% 
+%   Horizontal columned lists.
+% 
+% --------------------------------------------------------------------------
+% Clemens Niederberger
+% Web:    https://bitbucket.org/cgnieder/exsheets/
+% E-Mail: contact@mychemistry.eu
+% --------------------------------------------------------------------------
+% Copyright 2011-2013 Clemens Niederberger
+% 
+% This work may be distributed and/or modified under the
+% conditions of the LaTeX Project Public License, either version 1.3
+% of this license or (at your option) any later version.
+% The latest version of this license is in
+%   http://www.latex-project.org/lppl.txt
+% and version 1.3 or later is part of all distributions of LaTeX
+% version 2005/12/01 or later.
+% 
+% This work has the LPPL maintenance status `maintained'.
+% 
+% The Current Maintainer of this work is Clemens Niederberger.
+% --------------------------------------------------------------------------
+% The tasks package consists of the files
+%  - tasks.sty, tasks.cfg
+% --------------------------------------------------------------------------
+% If you have any ideas, questions, suggestions or bugs to report, please
+% feel free to contact me.
+% --------------------------------------------------------------------------
+\def\@tasks@date{2013/01/20}
+\def\@tasks@version{0.7}
+
+\RequirePackage { expl3 , xparse , l3keys2e }
+\ProvidesExplPackage
+  {tasks}
+  {\@tasks@date}
+  {\@tasks@version}
+  {Horizontal columned lists.}
+
+% requirements:
+\RequirePackage { epic , cntformats , xtemplate , environ }
+
+% variables:
+\seq_new:N    \l__tasks_seq
+
+\int_new:N    \l__tasks_depth_int
+\int_new:N    \g__tasks_int
+\int_new:N    \l__tasks_total_items_int
+\int_new:N    \l__tasks_columns_int
+\int_new:N    \l__tasks_rows_int
+
+\bool_new:N   \l__tasks_enumerate_bool
+\bool_new:N   \l__tasks_resume_bool
+\bool_new:N   \l__tasks_load_tasks_bool
+\bool_new:N   \l__tasks_label_width_bool
+\bool_new:N   \l__tasks_label_offset_bool
+
+\tl_new:N     \l__tasks_instance_tl
+\tl_new:N     \l__tasks_label_tl
+\tl_new:N     \l__tasks_label_pattern_tl
+\tl_new:N     \l__tasks_custom_label_format_tl
+\tl_new:N     \l__tasks_item_fill_left_tl
+\tl_new:N     \l__tasks_item_fill_right_tl
+\tl_new:N     \l__tasks_label_align_tl
+\tl_new:N     \task
+\tl_new:N     \l__tasks_item_tl
+\tl_new:N     \l__tasks_tmp_label_tl
+
+\dim_new:N    \l__tasks_item_indent_dim
+\dim_new:N    \l__tasks_item_width_dim
+\dim_new:N    \l__tasks_label_width_dim
+\dim_new:N    \l__tasks_label_default_width_dim
+\dim_new:N    \l__tasks_label_offset_dim
+\dim_new:N    \l__tasks_label_default_offset_dim
+
+\skip_new:N   \l__tasks_after_item_skip
+\skip_new:N   \l__tasks_before_list_skip
+\skip_new:N   \l__tasks_after_list_skip
+
+\NewCounterPattern* [ tasks ] { task } { tsk }
+\ReadCounterFrom [ tasks ] { task } \g__tasks_int
+
+% scratch variables:
+\tl_new:N     \l__tasks_tmpa_tl
+\int_new:N    \l__tasks_tmpa_int
+\coffin_new:N \l__tasks_tmpa_coffin
+\coffin_new:N \l__tasks_tmpb_coffin
+\coffin_new:N \l__tasks_tmpc_coffin
+
+% collect the tasks:
+\cs_new:Npn \__tasks_collect_tasks:nw #1#2 \end #3
+  {
+    \tl_put_right:Nn \l__tasks_body_tl { #1 }
+    \end { #3 }
+    \tl_if_eq:nnF { #1 } { #3 }
+      { \__tasks_collect_tasks:nw { #1 } }
+  }
+
+%  #1: instance
+%  #2: number of columns
+%  #3: item separator
+%  #4: environment body
+\cs_new:Npn \__tasks:nnnn #1#2#3#4
+  {
+    \seq_set_split:Nnn \l__tasks_seq { #3 } { #4 }
+    % remove the first (empty) item:
+    \seq_pop_left:NN \l__tasks_seq \l__tasks_tmpa_tl
+    \tl_if_blank:VF \l__tasks_tmpa_tl
+      { \tl_show:N \l__tasks_tmpa_tl \@noitemerr }
+    \int_set:Nn \l__tasks_total_items_int
+      { \seq_length:N \l__tasks_seq }
+    \UseInstance { tasks } { #1 }
+      { \l__tasks_total_items_int }
+      { #2 }
+      { \l__tasks_custom_label_format_tl }
+    % just to be sure:
+    \seq_clear:N \l__tasks_seq
+  }
+\cs_generate_variant:Nn \__tasks:nnnn { VnnV }
+
+\cs_new:Npn \__tasks_task:nnw #1#2[#3,#4][#5,#6](#7,#8)
+  {
+    \dim_set:Nn \l__tasks_item_width_dim
+      {
+        \linewidth / \l__tasks_columns_int -
+        \l__tasks_depth_int \l__tasks_item_indent_dim
+      }
+    \int_incr:N \l__tasks_tmpa_int
+    \__tasks_set_rows_num:NN
+      \l__tasks_total_items_int
+      \l__tasks_columns_int
+    \int_compare:nT { \l__tasks_tmpa_int > \l__tasks_columns_int }
+      { \int_set:Nn \l__tasks_tmpa_int { 1 } }
+    % the item:
+    \hcoffin_set:Nn \l__tasks_tmpa_coffin
+      {
+        \vcoffin_set:Nnn \l__tasks_tmpc_coffin
+          { \l__tasks_item_width_dim }
+          { \__tasks_setup: #2 }
+        \coffin_typeset:Nnnnn \l__tasks_tmpc_coffin
+          { l } { T } { 0pt } { 0pt }
+      }
+    % the label:
+    \vcoffin_set:Nnn \l__tasks_tmpb_coffin
+      { \l__tasks_label_width_dim }
+      {
+        \tl_use:N \l__tasks_item_fill_left_tl
+        \strut #1
+        \tl_use:N \l__tasks_item_fill_right_tl
+      }
+    \coffin_attach:NnnNnnnn
+      \l__tasks_tmpa_coffin { l } { T }
+      \l__tasks_tmpb_coffin { l } { T }
+      { -\l__tasks_label_width_dim - \l__tasks_label_offset_dim } { 0pt }
+    % typeset label & item:
+    % need this when a new row starts:
+    \int_compare:nT { \l__tasks_tmpa_int = 1 }
+      { \skip_vertical:N \c_zero_skip }
+    \skip_horizontal:N \l__tasks_item_indent_dim
+    \coffin_typeset:Nnnnn \l__tasks_tmpa_coffin
+      { l } { T } { 0pt } { 0pt }
+    % need this before a new row starts:
+    \int_compare:nT { \l__tasks_tmpa_int = \l__tasks_columns_int }
+      { \skip_vertical:N \l__tasks_after_item_skip }
+    \coffin_clear:N \l__tasks_tmpa_coffin
+    \coffin_clear:N \l__tasks_tmpb_coffin
+    \coffin_clear:N \l__tasks_tmpc_coffin
+  }
+\cs_generate_variant:Nn \__tasks_task:nnw { VV }
+
+\cs_new:Npn \__tasks_setup:
+  {
+    \dim_set:Nn \parskip { 0pt }
+    \skip_set:Nn \parfillskip { 0pt plus 1fil }
+    \dim_set_eq:NN \parskip \parsep
+    \dim_set_eq:NN \parindent \listparindent
+    \strut
+  }
+
+\cs_new:Npn \__tasks_set_rows_num:NN #1#2
+  {
+    \int_set:Nn \l__tasks_rows_int { \int_div_truncate:nn { #1 } { #2 } }
+    \int_compare:nNnT { \int_mod:nn { #1 } { #2 } } > { 0 }
+      { \int_incr:N \l__tasks_rows_int }
+  }
+
+\cs_new:Npn \__tasks_label_align:n #1
+  {
+    \clist_if_in:nnTF { left , center , right } { #1 }
+      {
+        \tl_if_eq:nnT { #1 } { left }
+          {
+            \tl_clear:N   \l__tasks_item_fill_left_tl
+            \tl_set_eq:NN \l__tasks_item_fill_right_tl \hfil
+          }
+        \tl_if_eq:nnT { #1 } { right }
+          {
+            \tl_set_eq:NN \l__tasks_item_fill_left_tl \hfill
+            \tl_clear:N   \l__tasks_item_fill_right_tl
+          }
+        \tl_if_eq:nnT { #1 } { center }
+          {
+            \tl_set_eq:NN \l__tasks_item_fill_left_tl  \hfil
+            \tl_set_eq:NN \l__tasks_item_fill_right_tl \hfil
+          }
+      }
+      {
+        \tl_clear:N   \l__tasks_item_fill_left_tl
+        \tl_set_eq:NN \l__tasks_item_fill_right_tl \hfil
+      }
+  }
+\cs_generate_variant:Nn \__tasks_label_align:n { V }
+\__tasks_label_align:n { left }
+
+% the `tasks' object:
+%   #1: number of items
+%   #2: number of columns
+%   #3: label-format
+\DeclareObjectType { tasks } { 3 }
+% the `default' template interface:
+\DeclareTemplateInterface { tasks } { default } { 3 }
+  {
+    enumerate       : boolean   = true    ,
+    label           : tokenlist           ,
+    indent          : length    = 2.5em   ,
+    label-format    : tokenlist = tsk[a]) ,
+    label-width     : length    = 3ex     ,
+    label-offset    : length    = 1ex     ,
+    after-item-skip : skip      = 1ex plus 1ex minus 1ex
+  }
+% the `default' template code:
+\DeclareTemplateCode { tasks } { default } { 3 }
+  {
+    enumerate       = \l__tasks_enumerate_bool           ,
+    label           = \l__tasks_label_tl                 ,
+    indent          = \l__tasks_item_indent_dim          ,
+    label-format    = \l__tasks_label_pattern_tl         ,
+    label-width     = \l__tasks_label_default_width_dim  ,
+    label-offset    = \l__tasks_label_default_offset_dim ,
+    after-item-skip = \l__tasks_after_item_skip
+  }
+  {
+    \AssignTemplateKeys
+    \bool_if:NF \l__tasks_label_width_bool
+      {
+        \dim_set_eq:NN
+          \l__tasks_label_width_dim
+          \l__tasks_label_default_width_dim
+      }
+    \bool_if:NF \l__tasks_label_offset_bool
+      {
+        \dim_set_eq:NN
+          \l__tasks_label_offset_dim
+          \l__tasks_label_default_offset_dim
+      }
+    \__tasks_label_align:V \l__tasks_label_align_tl
+    % need this for enumerate list:
+    \bool_if:nT { !\l__tasks_resume_bool && \l__tasks_enumerate_bool }
+      { \int_gzero:N \g__tasks_int }
+    \int_set:Nn \l__tasks_columns_int { #2 }
+    % set all the items in their own coffins and join with the ground:
+    \int_zero:N \l__tasks_tmpa_int
+    \tl_if_blank:VF \l__tasks_custom_label_format_tl
+      {
+        \tl_set_eq:NN
+          \l__tasks_label_pattern_tl
+          \l__tasks_custom_label_format_tl
+      }
+    \seq_map_inline:Nn \l__tasks_seq
+      {
+        \__tasks_read_item:w ##1 \q_stop
+        \bool_if:NTF \l__tasks_enumerate_bool
+          {
+            \int_gincr:N \g__tasks_int
+            \tl_if_blank:VT \l__tasks_label_tl
+              {
+                \tl_set:Nn \l__tasks_label_tl
+                  {
+                    \ReadCounterPatternFrom [ tasks ]
+                      \l__tasks_label_pattern_tl
+                  }
+              }
+          }
+          {
+            \tl_if_blank:VT \l__tasks_label_tl
+              { \tl_set_eq:NN \l__tasks_label_tl \labelitemi }
+          }
+        \tl_if_blank:VTF \l__tasks_tmp_label_tl
+          {
+            \__tasks_task:VVw
+              \l__tasks_label_tl
+              \l__tasks_item_tl
+              [ l , b ] [ l , t ] ( 0pt , 0pt )
+          }
+          {
+            \__tasks_task:VVw
+              \l__tasks_tmp_label_tl
+              \l__tasks_item_tl
+              [ l , b ] [ l , t ] ( 0pt , 0pt )
+            \tl_clear:N \l__tasks_tmp_label_tl
+          }
+      }
+  }
+
+\cs_new:Npn \__tasks_read_item:w
+  {
+    \peek_meaning:NTF [
+      { \__tasks_read_item_aux:w }
+      { \__tasks_read_item_aux:w[] }
+  }
+
+\cs_new:Npn \__tasks_read_item_aux:w [#1]#2 \q_stop
+  {
+    \tl_if_blank:nF { #1 }
+      { \tl_set:Nn \l__tasks_tmp_label_tl { #1 } }
+    \tl_set:Nn \l__tasks_item_tl { \ignorespaces #2 }
+  }
+
+% choice box:
+\bool_new:N \l__tasks_choice_checked_bool
+\dim_new:N  \l__tasks_choice_width_dim
+\dim_set:Nn \l__tasks_choice_width_dim { 1.25ex }
+\dim_new:N  \l__tasks_choice_linewidth_dim
+\dim_set:Nn \l__tasks_choice_linewidth_dim { .3pt }
+\dim_new:N  \l__tasks_choice_checkwidth_dim
+\dim_set:Nn \l__tasks_choice_checkwidth_dim { .5pt }
+\dim_new:N  \l__tasks_choice_raise_dim
+\dim_set:Nn \l__tasks_choice_raise_dim { .1ex }
+
+\cs_new:Npn \tasks_choice:
+  {
+    \leavevmode
+    \bool_set_false:N \l__tasks_choice_checked_bool
+    \box_move_up:nn
+      { \l__tasks_choice_raise_dim }
+      { \hbox:n { \__tasks_choice: } }
+  }
+
+\cs_new:Npn \tasks_choice_checked:
+  {
+    \leavevmode
+    \bool_set_true:N \l__tasks_choice_checked_bool
+    \box_move_up:nn
+      { \l__tasks_choice_raise_dim }
+      { \hbox:n { \__tasks_choice: } }
+  }
+
+\cs_new:Npn \__tasks_choice:
+  {%
+    \dim_set:Nn \unitlength { .1\l__tasks_choice_width_dim }
+    \begin{picture}(10,0)
+      \linethickness \l__tasks_choice_linewidth_dim
+      \drawline(0,0)(0,10)(10,10)(10,0)(0,0)
+      \linethickness \l__tasks_choice_checkwidth_dim
+      \bool_if:NT \l__tasks_choice_checked_bool
+        {
+          \drawline(2,2)(8,8)
+          \drawline(2,8)(8,2)
+        }
+    \end{picture}%
+  }
+
+\providecommand* \choicebox { \tasks_choice: }
+\providecommand* \checkedchoicebox { \tasks_choice_checked: }
+
+% base instance:
+% ALPHABETIZE: a) b) c)
+\DeclareInstance { tasks } { alphabetize } { default } { }
+
+\keys_define:nn { tasks / list }
+  {
+    style        .tl_set:N   = \l__tasks_instance_tl ,
+    label        .tl_set:N   = \l__tasks_custom_label_format_tl ,
+    label-width  .code:n     =
+      \dim_set:Nn \l__tasks_label_width_dim { #1 }
+      \bool_set_true:N \l__tasks_label_width_bool ,
+    label-offset .code:n     =
+      \dim_set:Nn \l__tasks_label_offset_dim { #1 }
+      \bool_set_true:N \l__tasks_label_offset_bool ,
+    label-align  .tl_set:N   = \l__tasks_label_align_tl ,
+    before-skip  .skip_set:N = \l__tasks_before_list_skip ,
+    after-skip   .skip_set:N = \l__tasks_after_list_skip ,
+    resume       .bool_set:N = \l__tasks_resume_bool
+  }
+
+% the generic environment:
+\NewEnviron { __tasks_env: } [ 3 ]
+  {
+    \keys_set:nn { tasks / list } { #2 }
+    \tl_if_blank:VT \l__tasks_instance_tl
+      { \keys_set:nn { tasks / list } { style = alphabetize } }
+    \skip_vertical:N \l__tasks_before_list_skip
+    \skip_vertical:N \c_zero_skip
+    \list {}
+      {
+        \dim_set:Nn \leftmargin { 0pt }
+        \dim_set:Nn \rightmargin { 0pt }
+      }
+    \item \scan_stop:
+    \int_incr:N \l__tasks_depth_int
+    \__tasks:VnnV \l__tasks_instance_tl { #3 } { #1 } \BODY
+    \endlist
+    \skip_vertical:N \l__tasks_after_list_skip
+  }
+
+% the user environment:
+\NewDocumentCommand \NewTasks { O{}mO{\task}D(){1} }
+  {
+    \NewDocumentEnvironment { #2 } { O{}D(){#4} }
+      { \__tasks_env: { #3 } { #1,##1 } { ##2 } }
+      { \end__tasks_env: }
+  }
+
+\NewDocumentCommand \RenewTasks { O{}mO{\task}D(){1} }
+  {
+    \RenewDocumentEnvironment { #2 } { O{}D(){#4} }
+      { \__tasks_env: { #3 } { #1,##1 } { ##2 } }
+      { \end__tasks_env: }
+  }
+
+% default list:
+\NewTasks { tasks }
+
+% package options:
+\keys_define:nn { tasks / options }
+  {
+    more .bool_set:N = \l__tasks_load_tasks_bool
+  }
+
+\ProcessKeysOptions { tasks / options }
+
+\bool_if:NT \l__tasks_load_tasks_bool
+  {
+    \cs_if_exist:NF \tasks_config_file_loaded:
+      { \input { tasks.cfg } }
+  }
+
+\cs_new:Npn \tasks_setup:n #1
+  { \keys_set:nn { tasks / list } { #1 } }
+
+\NewDocumentCommand \settasks { m }
+  { \tasks_setup:n { #1 } }
+
+\tex_endinput:D
\ No newline at end of file