carbohydrates (2dec15)

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diff --git a/Master/texmf-dist/doc/latex/carbohydrates/README b/Master/texmf-dist/doc/latex/carbohydrates/README
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+--------------------------------------------------------------------------
+the CARBOHYDRATES package v0.1 2015/12/01
+
+  ready drawn carbohydrates with chemfig
+
+--------------------------------------------------------------------------
+Clemens Niederberger
+Web:    https://github.com/cgnieder/carbohydrates/
+E-Mail: contact@mychemistry.eu
+--------------------------------------------------------------------------
+Copyright 2014-2015 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 carbohydrates package consists of the files
+ - carbohydrates.sty
+ - carbohydrates_en.tex, carbohydrates_en.pdf
+ - README
+--------------------------------------------------------------------------
+If you have any ideas, questions, suggestions or bugs to report, please
+feel free to contact me.
+--------------------------------------------------------------------------
+
diff --git a/Master/texmf-dist/doc/latex/carbohydrates/carbohydrates_en.pdf b/Master/texmf-dist/doc/latex/carbohydrates/carbohydrates_en.pdf
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diff --git a/Master/texmf-dist/doc/latex/carbohydrates/carbohydrates_en.tex b/Master/texmf-dist/doc/latex/carbohydrates/carbohydrates_en.tex
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+% arara: pdflatex
+% arara: biber
+% arara: pdflatex
+% arara: pdflatex
+\documentclass[load-preamble+]{cnltx-doc}
+\usepackage[utf8]{inputenc}
+\usepackage{carbohydrates}
+
+\setcnltx{
+  package  = {carbohydrates} ,
+  authors  = Clemens Niederberger ,
+  email    = contact@mychemistry.eu ,
+  info     = {carbohydrate molecules with \pkg*{chemfig}} ,
+  url      = https://github.com/cgnieder/carbohydrates/ ,
+  abstract = {%
+    \carbohydrates\ offers macros for making exercise sheets when teaching
+    carbohydrate chemistry a lot less tedious.  It uses \pkg{chemfig} for
+    drawing the formulas.
+  } ,
+  add-cmds = {
+    allose , altrose , arabinose ,
+    carbohydrate ,
+    desoxyribose ,
+    erythrose ,
+    galactose , glucose , glycerinaldehyde , gulose ,
+    idose ,
+    lyxose ,
+    mannose ,
+    newaldose ,
+    ribose ,
+    setcarbohydrates , setcarbohydratedefaults ,
+    talose , threose ,
+    xylose
+  } ,
+  add-silent-cmds = {
+    arrow ,
+    bondboldwidth , bondhashlength , bondwidth ,
+    D ,
+    chemfig , chemname , chemnameinit ,
+    definesubmol ,
+    iupac ,
+    printatom ,
+    schemestart , schemestop , setatomsep , setbondoffset , setbondstyle ,
+      setcrambond , setdoublesep
+  } ,
+  index-setup = { othercode = \footnotesize , level = \addsec } ,
+  makeindex-setup = { columns = 3 , columnsep = 1em }
+}
+
+\defbibheading{bibliography}[References]{\addsec{#1}}
+\addbibresource{\jobname.bib}
+
+\usepackage{filecontents}
+\begin{filecontents*}{\jobname.bib}
+@online{texdev,
+  url = {http://www.texdev.net/} ,
+  urldate = {2014-04-25} ,
+  author = {Joseph Wright}
+}
+\end{filecontents*}
+
+\usepackage{varioref}
+
+\usepackage{chemmacros}
+\chemsetup{greek=newtx}
+\newcommand*{\bondwidth}{0.06642 em}
+\newcommand*{\bondboldwidth}{0.22832 em}
+\newcommand*{\bondhashlength}{0.25737 em}
+\setdoublesep{0.35700 em}
+\setatomsep{1.78500 em}
+\setbondoffset{0.18265 em}
+\setbondstyle{line width = \bondwidth}
+\setcrambond
+  {\dimexpr\bondwidth*2 + \bondboldwidth\relax}
+  {\bondwidth}
+  {\bondhashlength}
+\renewcommand*\printatom[1]{{\small\ensuremath{\mathsf{#1}}}}
+
+\usepackage{rotating,array,tabu,booktabs}
+
+\defabbr\vs{\cnltxlatin{vs}}
+
+\begin{document}
+
+\section{Licence and Requirements}
+\license
+
+\carbohydrates\ loads the packages \pkg{chemfig}~\cite{pkg:chemfig},
+\pkg{etoolbox}~\cite{pkg:etoolbox} and \pkg{xcolor}~\cite{pkg:xcolor}.
+
+\section{The Idea}
+When teaching chemistry -- and in the case of this package: carbohydrate
+chemistry -- you have to show many examples of the basic aldoses and you have
+to explain the Fischer and the Haworth representation as well. This means you
+may have nearly the same \pkg{chemfig}~\cite{pkg:chemfig} formulas over and
+over in your documents.  \carbohydrates\ aims to ease this task.
+
+The following example will give a short impression of what the package does:
+\begin{example}
+  \glucose
+  \glucose[model={fischer=skeleton}]
+  \setatomsep{2.5em}
+  \glucose[model=haworth,ring]
+  \glucose[model=haworth,ring=furanose]
+\end{example}
+
+\section{Usage}
+\subsection{The Base Macro}
+\begin{commands}
+  \command{carbohydrate}[\oarg{options}\marg{spec}]
+    A generic macro for typesetting carbohydrates.
+\end{commands}
+We will talk about the options in a bit. First lets see what \meta{spec}
+means.  This argument is a series of the tokens \code{r}, \code{l} and
+\code{0} denoting an hydroxy group placed to the right or the left in the
+Fischer projection of the carbohydrate.  A \code{0} means that the hydroxy
+group is to be left out.  The series of tokens is meant to describe the
+hydroxy groups at the chiral centers. The aldehyde group\footnote{Also the
+  keto group once ketoses will be implemented.} and the hydroxy group at the
+end of the chain will be set automatically.  Unless specified otherwise the
+command expects a hexose which means a series of \emph{four} tokens.
+
+\begin{example}
+  \chemname{\carbohydrate{llrr}}{\iupac{\D-Mannose}}
+  \chemname{\carbohydrate[model={fischer=skeleton}]{llrr}}{\iupac{\D-Mannose}}
+  \setatomsep{2.5em}\chemnameinit{}
+  \chemname{\carbohydrate[model=chair]{llrr}}{\iupac{\D-Mannose}}
+  \chemname{\carbohydrate[model=haworth]{llrr}}{\iupac{\D-Mannose}}
+\end{example}
+
+Adding the option \option{pentose} means that now only \emph{three} tokens
+need to be specified.
+
+\begin{example}
+  \chemname{\carbohydrate[pentose]{rlr}}{\iupac{\D-Xylose}}
+  \chemname{\carbohydrate[pentose,model={fischer=skeleton}]{rlr}}{\iupac{\D-Xylose}}
+  \setatomsep{2.5em}\chemnameinit{}
+  \chemname{\carbohydrate[pentose,model=haworth,ring]{rlr}}{\iupac{\D-Xylose}}
+  \chemname{\carbohydrate[pentose,model=haworth,ring=pyranose]{rlr}}{\iupac{\D-Xylose}}
+\end{example}
+
+\subsection{Available Options}
+As you have already seen in the pevious examples \cs{carbohydrate} has an
+optional argument that takes different options.  Here is a complete list:
+\begin{options}
+  % model/fischer/skeleton/.code = \def\cbhdr@model{fischer@skeleton} ,
+  % model/fischer/full/.code     = \def\cbhdr@model{fischer} ,
+  \keychoice{model}{fischer,haworth,chair}\Default{fischer}
+    The model to be used to draw the molecule.  The choice \option{fischer}
+    is itself an option with two choices: \keyis{fischer}{skeleton} and
+    \keyis{fischer}{full}.  Leaving the choice out will use \code{full} as
+    default choice.
+  \opt{chain}
+    Draw the open chain isomer.
+  \keychoice{ring}{\default{true},pyranose,furanose}
+    Draw a ring isomer.  If you don't specify what ring type should be drawn
+    (\ie, if you choose \code{true}) the default depends on the length of the
+    carbohydrate.  For example for hexoses the default ring type is
+    \code{pyranose}.
+  \keychoice{anomer}{alpha,beta,undetermined}\Default{alpha}
+    The ring anomer.
+  \keychoice{length}{6,5,4,3}\Default{6}
+    The length of the carbohydrate.  \keyis{length}{6} draws a hexose,
+    \keyis{length}{3} draws a triose.
+  \opt{hexose}
+    An alias for \keyis{length}{6}.
+  \opt{pentose}
+    An alias for \keyis{length}{5}.
+  \opt{tetrose}
+   An alias for \keyis{length}{4}.
+  \opt{triose}
+    An alias for \keyis{length}{3}.
+  \keybool{3d}\Default{false}
+    Draw some of the bonds of the rings in the \code{haworth} and \code{chair}
+    models in a way that indicates the three dimensional structure of the
+    molecules.
+  \keylit-{color}{\marg{name}\marg{color}}
+    This option takes two arguments: \meta{name} specifies which part of the
+    molecule is to be colored, \meta{color} specifies the color to be used,
+    also see table~\vref{tab:color} and section~\ref{sec:colors}.
+\end{options}
+
+\begin{table}[htb]
+  \centering
+  \caption{Available names for the \option*{color} option.}\label{tab:color}
+  \begin{tabular}{>{\ttfamily}ll}
+    \toprule
+      \rmfamily\bfseries Name & \bfseries Function \\
+    \midrule
+      C1 & carbon 1 \\
+      C2 & carbon 2 \\
+      O-C2 & oxygen of the hydroxy group at carbon 2 \\
+      H-C2 & hydrogen of the hydroxy group at carbon 2 \\
+      C3 & carbon 3 \\
+      O-C3 & oxygen of the hydroxy group at carbon 3 \\
+      H-C3 & hydrogen of the hydroxy group at carbon 3 \\
+      C4 & carbon 4 \\
+      O-C4 & oxygen of the hydroxy group at carbon 4 \\
+      H-C4 & hydrogen of the hydroxy group at carbon 4 \\
+      C5 & carbon 5 \\
+      O-C5 & oxygen of the hydroxy group at carbon 5 \\
+      H-C5 & hydrogen of the hydroxy group at carbon 5 \\
+      C6 & carbon 6 \\
+      O-C6 & oxygen of the hydroxy group at carbon 6 \\
+      H-C6 & hydrogen of the hydroxy group at carbon 6 \\
+      anomerO & oxygen of the anomeric hydroxy group\slash aldehyde oxygen \\
+      anomerH & hydrogen of the anomeric hydroxy group \\
+      ringO & oxygen in the ring \\
+    \bottomrule
+  \end{tabular}
+\end{table}
+
+\subsection{Defining Shortcuts}\label{sec:defining-shortcuts}
+
+\carbohydrates\ allows to define shortcuts for aldoses:
+
+\begin{commands}
+  \command{newaldose}[\marg{cs}\oarg{options}\marg{spec}]
+    This defines the macro \meta{cs} with preset options \meta{options}.
+    \meta{spec} has the same meaning as for \cs{carbohydrate}.
+  \command{renewaldose}[\marg{cs}\oarg{options}\marg{spec}]
+    The same command but redefines an existing macro.
+\end{commands}
+
+In fact, \carbohydrates\ already defines macros for the common aldoses.  They
+are listed in table~\ref{tab:predefined-aldoses} on
+page~\pageref{tab:predefined-aldoses}.  They don't have any predefined options
+(except for \option{hexose}, \option{pentose} \etc).
+
+\begin{sidewaystable}
+  \setcarbohydrates{model={fischer=skeleton}}
+  \caption{Overview over the predefined aldoses.}
+  \label{tab:predefined-aldoses}
+  \begin{tabu}{*{8}{X[c]<{\strut}}}
+    \toprule
+      \allose & \altrose & \glucose   & \mannose &
+      \gulose & \idose   & \galactose & \talose \\
+      \cs{allose} & \cs{altrose} & \cs{glucose}   & \cs{mannose} &
+      \cs{gulose} & \cs{idose}   & \cs{galactose} & \cs{talose} \\
+      \iupac{\D-Allose}    & \iupac{\D-Altrose} &
+      \iupac{\D-Glucose}   & \iupac{\D-Mannose} &
+      \iupac{\D-Gulose}    & \iupac{\D-Idose} &
+      \iupac{\D-Galactose} & \iupac{\D-Talose} \\
+    \midrule
+      \ribose & \arabinose & \xylose & \lyxose & \desoxyribose \\
+      \cs{ribose} & \cs{arabinose} & \cs{xylose} & \cs{lyxose} &
+      \multicolumn{2}{l}{\cs{desoxyribose}} \\
+      \iupac{\D-Ribose} & \iupac{\D-Arabinose} &
+      \iupac{\D-Xylose} & \iupac{\D-Lyxose} &
+      \iupac{\D-Desoxy|ribose} \\
+    \midrule
+      \erythrose & \threose & \glycerinaldehyde \\
+      \cs{erythrose} & \cs{threose} & \multicolumn{2}{l}{\cs{glycerinaldehyde}} \\
+      \iupac{\D-Erythrose} & \iupac{\D-Threose} &
+      \iupac{\D-Glycerin|aldehyde} \\
+    \bottomrule
+  \end{tabu}
+\end{sidewaystable}
+
+\subsection{Available Models}\label{sec:available-models}
+
+\carbohydrates\ implements different models for drawing carbohydrates:
+\begin{itemize}
+  \item Fischer -- skeleton: the Fischer representation with only a skeleton
+    formula.
+  \item Fischer -- full: the Fischer representation including all C and H
+    atoms.
+  \item Haworth: the Haworth representation.
+  \item Chair: the chair conformation.
+\end{itemize}
+
+While the Fischer model is implemented for all carbohydrates both Haworth and
+chair are not.  The chair model is only implemented for aldohexoses, Haworth
+is implemented for aldotetroses, -pentoses and -hexoses.
+
+\begin{example}
+  \glucose[model={fischer=skeleton}]
+  \glucose[model={fischer=full}]
+  \setatomsep{2.5em}
+  \glucose[model=haworth]
+  \glucose[model=chair]
+\end{example}
+
+\subsection{Chain \vs\ Ring Forms}
+
+While the chain forms are available in all models the ring forms obviously
+aren't.  There are two ring forms for hexoses and pentoses: pyranoses and
+furanoses.  For tetroses only the furanose rings are available as there don't
+exist pyranose ring forms (for obvious reasons).  It is also clear that
+neither pyranose nor furanose forms of trioses exist.
+
+\begin{example}
+  \setatomsep{2.5em}
+  \glucose[model=haworth,ring]
+  \ribose[model=haworth,ring]
+  \threose[model=haworth,ring]
+\end{example}
+
+\textbf{Actually the above is not true: the chain forms are not available in all
+models for all aldoses.  As said in section~\ref{sec:available-models} the
+chair model is only implemented for aldohexoses.  Also chains are not
+implemented for tetroses and trioses in the Haworth model.}
+
+\subsection{Default Settings}
+\begin{commands}
+  \command{setcarbohydrate}[\marg{options}]
+    Set package options for all carbohydrates within the current scope.
+  \command{setcarbohydratedefaults}[\marg{csname}\marg{options}]
+    Set options for a predefined carbohydrate within the current scope. The
+    first argument \meta{csname} is the macro name of the shortcut (see
+    section~\ref{sec:defining-shortcuts}).
+\end{commands}
+
+\begin{example}
+  \setatomsep{2.5em}
+  \setcarbohydratedefaults\glucose{ring,model=haworth,anomer=undetermined}
+  \glucose\
+  \mannose
+\end{example}
+
+\subsection{Colors}\label{sec:colors}
+For educating purposes it may be useful to be able to color certain atoms. The
+\option{color} option allows this.
+\begin{example}
+  \setcarbohydrates{model=chair}
+  \setatomsep{2.5em}
+  \schemestart
+    \glucose[color={anomerO}{red},color={O-C5}{green},color={H-C5}{blue}]
+    \arrow{<=>}
+    \glucose[ring,color={anomerO}{red},color={ringO}{green},color={anomerH}{blue}]
+  \schemestop
+\end{example}
+
+\section{\texorpdfstring{\textsc{todo}}{TODO}s}
+There are still quite a number of missing features that I'd like to implement
+some day such as
+\begin{itemize}
+  \item ring forms for \laevus-carbohydrates,
+  \item support for both chair conformations and the boat conformation,
+  \item support for ketoses,
+  \item support for oxidized and reduzed forms, and
+  \item disaccharides.
+\end{itemize}
+There is \emph{no} time table, though -- wether these features will be implemented
+any time soon or at all is undecided.
+
+\section{About the Examples in this Manual}
+All macros used in the examples either belong to \carbohydrates\ and are
+described in this manual or they belong to either
+\pkg{chemfig}~\cite{pkg:chemfig}, \pkg{chemmacros}~\cite{pkg:chemmacros},
+\pkg{chemformula}~\cite{pkg:chemformula}, or are standard \LaTeX\ macros.  I
+encourage you to take a look at the packages for typesetting chemistry
+documents.
+
+The \pkg{chemfig} settings have been adjusted for the examples in this
+manual.  Specifically the preamble of this document makes these settings:
+
+\begin{sourcecode}
+  \newcommand*{\bondwidth}{0.06642 em}
+  \newcommand*{\bondboldwidth}{0.22832 em}
+  \newcommand*{\bondhashlength}{0.25737 em}
+  \setdoublesep{0.35700 em}
+  \setatomsep{1.78500 em}
+  \setbondoffset{0.18265 em}
+  \setbondstyle{line width = \bondwidth}
+  \setcrambond
+    {\dimexpr\bondwidth*2 + \bondboldwidth\relax}
+    {\bondwidth}
+    {\bondhashlength}
+  \renewcommand*\printatom[1]{{\small\ensuremath{\mathsf{#1}}}}
+\end{sourcecode}
+These settings are taken from~\cite{texdev}.  Search the page for
+\code{chemfig} and you should be able to find them there.
+
+\end{document}
diff --git a/Master/texmf-dist/doc/latex/carbohydrates/test.tex b/Master/texmf-dist/doc/latex/carbohydrates/test.tex
new file mode 100644
index 00000000000..a5bd6041f57
--- /dev/null
+++ b/Master/texmf-dist/doc/latex/carbohydrates/test.tex
@@ -0,0 +1,143 @@
+\documentclass{scrartcl}
+\usepackage{carbohydrates}
+% \setcarbohydrates{
+%   color={anomerO}{red} ,
+%   color={anomerH}{blue} ,
+%   color={ringO}{green} ,
+%   color={C2}{yellow} ,
+%   color={O-C2}{yellow} ,
+%   color={H-C2}{yellow} ,
+%   color={C5}{purple} ,
+%   color={O-C5}{purple} ,
+%   color={H-C5}{purple} ,
+%   color={C6}{orange} ,
+%   color={O-C6}{orange} ,
+%   color={H-C6}{orange}
+% }
+
+\begin{document}
+
+\setcarbohydrates{model=chair}
+\schemestart
+  \glucose[color={anomerO}{red},color={O-C5}{green},color={H-C5}{blue}]
+  \arrow{<=>}
+  \glucose[ring,color={anomerO}{red},color={ringO}{green},color={anomerH}{blue}]
+\schemestop
+
+\end{document}
+
+\documentclass{scrartcl}
+
+\usepackage{carbohydrates}
+\colorlet{cbhdr@anomerO}{green}
+\colorlet{anomerH}{blue}
+\colorlet{cbhdr@ringO}{red}
+\colorlet{cbhdr@O-C5}{orange}
+\colorlet{cbhdr@H-C5}{yellow}
+
+\begin{document}
+
+\glucose[model=haworth,chain]
+
+\ribose[model=haworth,chain]
+
+\ribose[model=haworth,ring]
+
+\end{document}
+
+\glucose[model={fischer=skeleton}]
+\quad
+\glucose[model={fischer=skeleton},ring]
+
+\bigskip
+
+\threose[model={fischer=skeleton}]
+\quad
+\threose[ring,model=haworth]
+
+% \glycerinaldehyde[ring]
+
+\bigskip
+
+\ribose[ring=pyranose]
+\quad
+\ribose[model=haworth,ring]
+\quad
+\ribose[model=haworth,ring=pyranose]
+
+\bigskip
+
+\carbohydrate[model=haworth,ring=furanose,]{l0ll}
+
+\end{document}
+% \makeatletter
+
+\glucose
+\quad
+\glucose[ring]
+\quad
+\glucose[ring,anomer=beta]
+
+\bigskip
+
+\glucose[ring=furanose]
+\quad
+\glucose[ring=furanose,model=haworth]
+\quad
+\galactose[ring=furanose,model=haworth]
+
+\end{document}
+
+\bigskip
+
+\glucose[model={fischer=skeleton}]
+\quad
+\glucose[model={fischer=skeleton},ring]
+\quad
+\glucose[model={fischer=skeleton},ring,anomer=beta]
+
+\bigskip
+
+\glucose[model=haworth]
+\quad
+\glucose[model=haworth,ring]
+\quad
+\glucose[model=haworth,ring,anomer=beta]
+
+\bigskip
+
+\glucose[model=chair]
+\quad
+\glucose[model=chair,ring]
+\quad
+\glucose[model=chair,ring,anomer=beta]
+
+\glucose[model=haworth,ring,anomer=undetermined]
+
+\bigskip
+
+\idose[model=haworth]
+\quad
+\idose[model=haworth,ring]
+\quad
+\idose[model=haworth,ring,anomer=beta]
+
+\bigskip
+
+\idose[model=chair]
+\quad
+\idose[model=chair,ring]
+\quad
+\idose[model=chair,ring,anomer=beta]
+
+\bigskip
+
+\ribose
+\quad
+\desoxyribose
+\quad
+\desoxyribose[model={fischer=skeleton},ring]
+
+
+\end{document}
+
diff --git a/Master/texmf-dist/tex/latex/carbohydrates/carbohydrates.sty b/Master/texmf-dist/tex/latex/carbohydrates/carbohydrates.sty
new file mode 100644
index 00000000000..2e1814bab76
--- /dev/null
+++ b/Master/texmf-dist/tex/latex/carbohydrates/carbohydrates.sty
@@ -0,0 +1,874 @@
+% --------------------------------------------------------------------------
+% the CARBOHYDRATES package
+% 
+%   ready drawn carbohydrates with chemfig
+%
+% --------------------------------------------------------------------------
+% Clemens Niederberger
+% Web:    https://github.com/cgnieder/carbohydrates
+% E-Mail: contact@mychemistry.eu
+% --------------------------------------------------------------------------
+% Copyright 2014-2015 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.
+% --------------------------------------------------------------------------
+% If you have any ideas, questions, suggestions or bugs to report, please
+% feel free to contact me.
+% --------------------------------------------------------------------------
+\def\cbhdr@date{2015/12/01}
+\def\cbhdr@version{v0.1}
+\def\cbhdr@info{carbohydrate molecules with chemfig}
+
+\ProvidesPackage{carbohydrates}[%
+  \cbhdr@date\space
+  \cbhdr@version\space
+  \cbhdr@info\space (CN)]
+
+\RequirePackage{etoolbox}
+\RequirePackage{chemfig,xcolor}
+
+% ==========================================================================
+% message handling
+% generic help message:
+\newrobustcmd\cbhdr@create@message[2]{%
+  \ifstrequal{#1}{Error}
+    {%
+      \lowercase{\csdef{cbhdr@#1}}##1{%
+        \csuse{Package#1}{carbohydrates}{##1}{#2}}%
+    }{%
+      \lowercase{\csdef{cbhdr@#1}}##1{%
+        \csuse{Package#1}{carbohydrates}{##1}}%
+    }}
+
+\newcommand*\cbhdr@error@message{%
+  For details have a look at the `carbohydrates' manual.%
+}
+
+% create message macros:
+\cbhdr@create@message{Error}{\cbhdr@error@message}
+\cbhdr@create@message{Warning}{}
+\cbhdr@create@message{WarningNoLine}{}
+\cbhdr@create@message{Info}{}
+
+\newcommand*\cbhdr@ring@error[2]{%
+  \cbhdr@error{#1 can't form #2 rings}%
+}
+
+\newcommand*\cbhdr@define@ring@error[3]{%
+  \protected\csdef{cbhdr@aldo#2@#1@ring@#3}{\cbhdr@ring@error{#2s}{#3}}%
+}
+
+\newcommand*\cbhdr@define@chain@error[2]{%
+  \protected\csdef{cbhdr@aldo#2@#1@chain}{%
+    \cbhdr@error{The chain is not implemented for #2s in the #1 model}%
+  }%
+}
+
+\newcommand*\cbhdr@chair@error[1]{%
+  \cbhdr@error{The chair model is not implemented for #1}%
+}
+
+\newcommand*\cbhdr@define@chair@errors[1]{%
+  \protected\csdef{cbhdr@aldo#1@chair@chain}{\cbhdr@chair@error{#1s}}%
+  \protected\csdef{cbhdr@aldo#1@chair@ring@pyranose}{\cbhdr@chair@error{#1s}}%
+  \protected\csdef{cbhdr@aldo#1@chair@ring@furanose}{\cbhdr@chair@error{#1s}}%
+}
+
+\newrobustcmd\cbhdr@expand@x[2]{%
+  \begingroup\edef\cbhdr@expand@tmp{\endgroup\unexpanded{#1}{#2}}%
+  \cbhdr@expand@tmp
+}
+\newrobustcmd\cbhdr@expand@nx[3]{%
+  \begingroup\edef\cbhdr@expand@tmp{\endgroup\unexpanded{#1{#2}}{#3}}%
+  \cbhdr@expand@tmp
+}
+
+\newcommand*\cbhdr@stripbs{\expandafter\@gobble\string}
+
+% ==========================================================================
+% colors
+\newrobustcmd*\cbhdr@defcolor[2]{\colorlet{cbhdr@#1}{#2}}
+
+\cbhdr@defcolor{C1}{black}
+\cbhdr@defcolor{C6}{black}
+\cbhdr@defcolor{O-C6}{black}
+\cbhdr@defcolor{H-C6}{black}
+\cbhdr@defcolor{anomerO}{black}
+\cbhdr@defcolor{anomerH}{black}
+\cbhdr@defcolor{ringO}{black}
+
+\newcommand*\cbhdr@atom@color[2]{\unexpanded{\textcolor{cbhdr@#1}{#2}}}
+
+% ==========================================================================
+% wavy bonds:
+\usetikzlibrary{decorations.pathmorphing}
+\pgfdeclaredecoration{cbhdr wave}{initial}{
+  \state{initial}[
+    width = +0pt ,
+    next state = sine,
+    persistent precomputation = {
+      \pgfmathsetmacro\matchinglength{
+        \pgfdecoratedinputsegmentlength /
+        int(\pgfdecoratedinputsegmentlength/\pgfdecorationsegmentlength)
+      }
+      \setlength{\pgfdecorationsegmentlength}{\matchinglength pt}
+    }
+  ]{}
+  \state{sine}[width=\pgfdecorationsegmentlength]{
+    \pgfpathsine{
+      \pgfpoint
+        {0.25\pgfdecorationsegmentlength}
+        {0.5\pgfdecorationsegmentamplitude}
+      }
+    \pgfpathcosine{
+      \pgfpoint
+        {0.25\pgfdecorationsegmentlength}
+        {-0.5\pgfdecorationsegmentamplitude}
+      }
+    \pgfpathsine{
+      \pgfpoint
+        {0.25\pgfdecorationsegmentlength}
+        {-0.5\pgfdecorationsegmentamplitude}
+      }
+    \pgfpathcosine{
+      \pgfpoint
+        {0.25\pgfdecorationsegmentlength}
+        {0.5\pgfdecorationsegmentamplitude}
+      }
+  }
+  \state{final}{}
+}
+
+\tikzset{
+  cbhdr/wavy bond/.style =
+    {
+      decorate,
+      decoration =
+        {
+          amplitude   = 0.23*\CF@atom@sep/3 ,
+          post length = 0 pt,
+          pre length  = 0 pt,
+          % Use the atom spacing: saved 
+          segment length = \CF@atom@sep/5 ,
+          cbhdr wave
+        }
+    }
+}
+
+% ==========================================================================
+% sub molecules for all the modular building of the molecules later
+\newcommand*\cbhdr@C[1]{\cbhdr@atom@color{C#1}{C}}
+
+\newcommand*\cbhdr@OH[1]{%
+  \cbhdr@atom@color{O-C#1}{O}|%
+  \cbhdr@atom@color{H-C#1}{H}%
+}
+\newcommand*\cbhdr@HO[1]{%
+  \cbhdr@atom@color{H-C#1}{H}|%
+  \cbhdr@atom@color{O-C#1}{O}%
+}
+\newcommand*\cbhdr@ring@O{\cbhdr@atom@color{ringO}{O}}
+\newcommand*\cbhdr@anomer@O{\cbhdr@atom@color{anomerO}{O}}
+\newcommand*\cbhdr@anomer@OH{%
+  \cbhdr@atom@color{anomerO}{O}|%
+  \cbhdr@atom@color{anomerH}{H}%
+}
+\newcommand*\cbhdr@anomer@HO{%
+  \cbhdr@atom@color{anomerH}{H}|%
+  \cbhdr@atom@color{anomerO}{O}%
+}
+
+\newrobustcmd*\cbhdr@definesubmol@expand{\cbhdr@expand@nx\definesubmol}
+\newrobustcmd*\cbhdr@chemfig@expand{\cbhdr@expand@x\chemfig}
+
+\newrobustcmd\cbhdr@define@Csubmols[1]{%
+  \cbhdr@defcolor{O-C#1}{black}%
+  \cbhdr@defcolor{H-C#1}{black}%
+  \cbhdr@defcolor{C#1}{black}%
+  % aldohexoses:
+  % fischer:
+  % skeletons
+  \cbhdr@definesubmol@expand{cbhdr@fischer@skeleton@C#1@OHr}{(-[:0]\cbhdr@OH{#1})}%
+  \cbhdr@definesubmol@expand{cbhdr@fischer@skeleton@C#1@OHl}{(-[:180]\cbhdr@HO{#1})}%
+  \cbhdr@definesubmol@expand{cbhdr@fischer@skeleton@C#1@OH0}{}%
+  % with C and H
+  \cbhdr@definesubmol@expand{cbhdr@fischer@C#1@OHr}{(-[:0]\cbhdr@OH{#1})(-[:180]H)}%
+  \cbhdr@definesubmol@expand{cbhdr@fischer@C#1@OHl}{(-[:180]\cbhdr@HO{#1})(-[:0]H)}%
+  \cbhdr@definesubmol@expand{cbhdr@fischer@C#1@OH0}{(-[:180]H)(-[:0]H)}%
+  % haworth:
+  \ifnum#1=5\relax
+    \cbhdr@definesubmol@expand{cbhdr@haworth@C#1@OHr}{(-[:0]\cbhdr@OH{#1})}%
+    \cbhdr@definesubmol@expand{cbhdr@haworth@C#1@OHl}{(-[:180,.5]\cbhdr@HO{#1})}%
+  \else
+    \cbhdr@definesubmol@expand{cbhdr@haworth@C#1@OHr}{(-[:-90,.5,,1]\cbhdr@OH{#1})}%
+    \cbhdr@definesubmol@expand{cbhdr@haworth@C#1@OHl}{(-[:90,.5,,1]\cbhdr@OH{#1})}%
+  \fi
+  \definesubmol{cbhdr@haworth@C#1@OH0}{}%
+  % chair:
+  \ifcase#1
+  \or % 1
+  \or % 2
+    \cbhdr@definesubmol@expand{cbhdr@chair@C#1@OHr}{(-[:-55,.75,,1]\cbhdr@OH{#1})}%
+    \cbhdr@definesubmol@expand{cbhdr@chair@C#1@OHl}{(-[:90,.5,,1]\cbhdr@OH{#1})}%
+  \or % 3
+    \cbhdr@definesubmol@expand{cbhdr@chair@C#1@OHr}{(-[:-90,.5,,1]\cbhdr@OH{#1})}%
+    \cbhdr@definesubmol@expand{cbhdr@chair@C#1@OHl}{(-[:170,.75,,2]\cbhdr@HO{#1})}%
+  \or % 4
+    \cbhdr@definesubmol@expand{cbhdr@chair@C#1@OHr}{(-[:190,.75,,2]\cbhdr@HO{#1})}%
+    \cbhdr@definesubmol@expand{cbhdr@chair@C#1@OHl}{(-[:90,.5,,1]\cbhdr@OH{#1})}%
+  \or % 5
+    \cbhdr@definesubmol@expand{cbhdr@chair@C#1@OHr}{(-[:10,.75,,1]\cbhdr@OH{#1})}%
+    \cbhdr@definesubmol@expand{cbhdr@chair@C#1@OHl}{(-[:-90,.5,,1]\cbhdr@OH{#1})}%
+  \fi
+  \definesubmol{cbhdr@chair@C#1@OH0}{}%
+}
+\cbhdr@define@Csubmols{2}
+\cbhdr@define@Csubmols{3}
+\cbhdr@define@Csubmols{4}
+\cbhdr@define@Csubmols{5}
+
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C2@OHr}{(-[:-90,.5]\cbhdr@OH{2})}
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C2@OHl}{(-[:90,.5,,2]\cbhdr@HO{2})}
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C2@OH0}{}
+
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C3@OHr}{(-[:-90,.5]\cbhdr@OH{3})}
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C3@OHl}{(-[:90,.5]\cbhdr@OH{3})}
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C3@OH0}{}
+
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C4@OHr}{(-[:20]\cbhdr@OH{4})}
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C4@OH0}{}
+
+% 4=r, 5=r
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C4@OHr@C5@OHr}{(
+  -[:90,.5](<[:30,.5]\cbhdr@OH{5})
+  -[:120,.5]
+  -[:-180,.5,,2]HO
+)}
+% 4=l, 5=r
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C4@OHl@C5@OHr}{(
+  -[:-90,.5](<:[:150,.5]\cbhdr@HO{5})
+  -[:-120,.5]
+  -[:180,.5,,2]HO
+)}
+
+% 4=r, 5=l
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C4@OHr@C5@OHl}{(
+  -[:90,.5](<:[:30,.5]\cbhdr@OH{5})
+  -[:120,.5]
+  -[:-180,.5,,2]HO
+)}
+% 4=l, 5=l
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C4@OHl@C5@OHl}{(
+  -[:-90,.5](<[:150,.5]\cbhdr@HO{5})
+  -[:-120,.5]
+  -[:180,.5,,2]HO
+)}
+
+% 4=r, 5=0
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C4@OHr@C5@OH0}{(
+  -[:90,.5]
+  -[:120,.5]
+  -[:-180,.5]HO
+)}
+% 4=l, 5=0
+\cbhdr@definesubmol@expand{cbhdr@haworth@furanose@C4@OHl@C5@OH0}{(
+  -[:-90,.5]
+  -[:-120,.5]
+  -[:180,.5]HO
+)}
+% 4=0 wouldn't make sense since then the furanose ring cannot be formed
+
+% fischer
+\cbhdr@definesubmol@expand{cbhdr@fischer@skeleton@aldehyde}{(=_[:30]\cbhdr@anomer@O)}
+\cbhdr@definesubmol@expand{cbhdr@fischer@skeleton@OHalpha}{(-[:0]\cbhdr@anomer@OH)}
+\cbhdr@definesubmol@expand{cbhdr@fischer@skeleton@OHbeta}{(-[:180]\cbhdr@anomer@HO)}
+\cbhdr@definesubmol@expand{cbhdr@fischer@skeleton@OHundetermined}{(-[:0]\cbhdr@anomer@OH)}
+
+\cbhdr@definesubmol@expand{cbhdr@fischer@aldehyde}{(=[:30]\cbhdr@anomer@O)(-[:150]H)}
+\cbhdr@definesubmol@expand{cbhdr@fischer@OHalpha}{(-[:0]\cbhdr@anomer@OH)(-[:180]H)}
+\cbhdr@definesubmol@expand{cbhdr@fischer@OHbeta}{(-[:180]\cbhdr@anomer@HO)(-[:0]H)}
+\cbhdr@definesubmol@expand{cbhdr@fischer@OHundetermined}{(-[:0]\cbhdr@anomer@HO)(-[:180]H)}
+
+% haworth
+\cbhdr@definesubmol@expand{cbhdr@haworth@OHalpha}{(-[:-90,.5,,1]\cbhdr@anomer@OH)}
+\cbhdr@definesubmol@expand{cbhdr@haworth@OHbeta}{(-[:90,.5,,1]\cbhdr@anomer@OH)}
+\cbhdr@definesubmol@expand{cbhdr@haworth@OHundetermined}
+  {(-[:0,.75,,1,cbhdr/wavy bond]\cbhdr@anomer@OH)}
+
+% chair:
+\cbhdr@definesubmol@expand{cbhdr@chair@OHalpha}{(-[:-90,.5,,1]\cbhdr@anomer@OH)}
+\cbhdr@definesubmol@expand{cbhdr@chair@OHbeta}{(-[:10,.75,,1]\cbhdr@anomer@OH)}
+\cbhdr@definesubmol@expand{cbhdr@chair@OHundetermined}
+  {(-[:0,.75,,1,cbhdr/wavy bond]\cbhdr@anomer@OH)}
+
+% ==========================================================================
+% commands to define the chain and ring molecules avoiding code duplication:
+
+% the arguments of a chain refer to r and l for the chiral centers. A hexose
+% needs four arguments: \cbhdr@newchain\hexose#1#2#3#4{<code>}
+
+% \cbhdr@newchain<macro><arguments>{<chemfig code>}
+
+\protected\def\cbhdr@newchain#1{\cbhdr@newchain@aux@i{#1}}
+\protected\def\cbhdr@newchain@aux@i#1#2#{\cbhdr@newchain@aux@ii{#1}{#2}}
+\protected\def\cbhdr@newchain@aux@ii#1#2#3{%
+  \protected\csdef{\cbhdr@stripbs#1@aux}#2\q@stop{\cbhdr@chemfig@expand{#3}}%
+  \newrobustcmd*#1[1]{\csuse{\cbhdr@stripbs#1@aux}##1\q@stop}%
+}
+
+% the first argument of a ring always is alpha/beta, the following arguments
+% refer to r and l for the chiral centers. A hexose needs five arguments:
+% \cbhdr@newring\hexose#1#2#3#4#5{<code>}
+
+% \cbhdr@newring<macro><arguments>{<chemfig code>}
+
+\protected\def\cbhdr@newring#1{\cbhdr@newring@aux@i{#1}}
+\protected\def\cbhdr@newring@aux@i#1#2#{\cbhdr@newring@aux@ii{#1}{#2}}
+\protected\def\cbhdr@newring@aux@ii#1#2#3{%
+  \protected\csdef{\cbhdr@stripbs#1@aux}#2\q@stop{\cbhdr@chemfig@expand{#3}}%
+  \newrobustcmd*#1[1]{\csuse{\cbhdr@stripbs#1@aux}{\cbhdr@anomer}##1\q@stop}%
+}
+
+% ==========================================================================
+% now let's build the molecules using the submolecules from above. They're
+% all named using the following naming scheme:
+%
+% \<module>@<model>@<chain>/<ring>(@<ringtype>)
+%
+% --------------------------------------------------------------------------
+% Fischer - skeleton formulas
+
+%%%
+% hexoses
+% chain
+\cbhdr@newchain\cbhdr@aldohexose@fischer@skeleton@chain#1#2#3#4{
+  !{cbhdr@fischer@skeleton@aldehyde}
+  -[:-90]!{cbhdr@fischer@skeleton@C2@OH#1}
+  -[:-90]!{cbhdr@fischer@skeleton@C3@OH#2}
+  -[:-90]!{cbhdr@fischer@skeleton@C4@OH#3}
+  -[:-90]!{cbhdr@fischer@skeleton@C5@OH#4}
+  -[:-90](-[:0]\cbhdr@OH{6})
+}
+
+% pyranoses
+\cbhdr@newring\cbhdr@aldohexose@fischer@skeleton@ring@pyranose#1#2#3#4#5{%
+  !{cbhdr@fischer@skeleton@OH#1}(-[:90]-[:0]-?)
+  -[:-90]!{cbhdr@fischer@skeleton@C2@OH#2}
+  -[:-90]!{cbhdr@fischer@skeleton@C3@OH#3}
+  -[:-90]!{cbhdr@fischer@skeleton@C4@OH#4}
+  -[:-90](-[:0]\cbhdr@ring@O-?)
+  -[:-90](-[:0]\cbhdr@OH{6})
+}
+
+% furanoses
+\cbhdr@newring\cbhdr@aldohexose@fischer@skeleton@ring@furanose#1#2#3#4#5{%
+  !{cbhdr@fischer@skeleton@OH#1}(-[:90]-[:0]-?)
+  -[:-90]!{cbhdr@fischer@skeleton@C2@OH#2}
+  -[:-90]!{cbhdr@fischer@skeleton@C3@OH#3}
+  -[:-90](-[:0]\cbhdr@ring@O-?)
+  -[:-90]!{cbhdr@fischer@skeleton@C5@OH#5}
+  -[:-90](-[:0]\cbhdr@OH{6})
+}
+
+%%%
+% pentoses
+% chain
+\cbhdr@newchain\cbhdr@aldopentose@fischer@skeleton@chain#1#2#3{%
+  !{cbhdr@fischer@skeleton@aldehyde}
+  -[:-90]!{cbhdr@fischer@skeleton@C2@OH#1}
+  -[:-90]!{cbhdr@fischer@skeleton@C3@OH#2}
+  -[:-90]!{cbhdr@fischer@skeleton@C4@OH#3}
+  -[:-90](-[:0]\cbhdr@OH{5})
+}
+
+% pyranoses
+\cbhdr@newring\cbhdr@aldopentose@fischer@skeleton@ring@pyranose#1#2#3#4{%
+  !{cbhdr@fischer@skeleton@OH#1}(-[:90]-[:0]-?)
+  -[:-90]!{cbhdr@fischer@skeleton@C2@OH#2}
+  -[:-90]!{cbhdr@fischer@skeleton@C3@OH#3}
+  -[:-90]!{cbhdr@fischer@skeleton@C4@OH#4}
+  -[:-90](-[:0]\cbhdr@ring@O-?)
+}
+
+% furanoses
+\cbhdr@newring\cbhdr@aldopentose@fischer@skeleton@ring@furanose#1#2#3#4{%
+  !{cbhdr@fischer@skeleton@OH#1}(-[:90]-[:0]-?)
+  -[:-90]!{cbhdr@fischer@skeleton@C2@OH#2}
+  -[:-90]!{cbhdr@fischer@skeleton@C3@OH#3}
+  -[:-90](-[:0]\cbhdr@ring@O-?)
+  -[:-90](-[:0]\cbhdr@OH{5})
+}
+
+%%%
+% tetroses
+% chain
+\cbhdr@newchain\cbhdr@aldotetrose@fischer@skeleton@chain#1#2{%
+  !{cbhdr@fischer@skeleton@aldehyde}
+  -[:-90]!{cbhdr@fischer@skeleton@C2@OH#1}
+  -[:-90]!{cbhdr@fischer@skeleton@C3@OH#2}
+  -[:-90](-[:0]\cbhdr@OH{4})
+}
+
+% pyranoses
+\cbhdr@define@ring@error{fischer@skeleton}{tetrose}{pyranose}
+
+% furanoses
+\cbhdr@newring\cbhdr@aldotetrose@fischer@skeleton@ring@furanose#1#2#3{%
+  !{cbhdr@fischer@skeleton@OH#1}(-[:90]-[:0]-?)
+  -[:-90]!{cbhdr@fischer@skeleton@C2@OH#2}
+  -[:-90]!{cbhdr@fischer@skeleton@C3@OH#3}
+  -[:-90](-[:0]\cbhdr@ring@O-?)
+}
+
+%%%
+% trioses
+% chain
+\cbhdr@newchain\cbhdr@aldotriose@fischer@skeleton@chain#1{%
+  !{cbhdr@fischer@skeleton@aldehyde}
+  -[:-90]!{cbhdr@fischer@skeleton@C2@OH#1}
+  -[:-90](-[:0]\cbhdr@OH{3})
+}
+
+% pyranoses
+\cbhdr@define@ring@error{fischer@skeleton}{triose}{pyranose}
+
+% furanoses
+\cbhdr@define@ring@error{fischer@skeleton}{triose}{furanose}
+
+% --------------------------------------------------------------------------
+% Fischer - with C and H
+
+%%%
+% hexoses
+% chain
+\cbhdr@newchain\cbhdr@aldohexose@fischer@chain#1#2#3#4{%
+  \cbhdr@C{1}!{cbhdr@fischer@aldehyde}
+  -[:-90]\cbhdr@C{2}!{cbhdr@fischer@C2@OH#1}
+  -[:-90]\cbhdr@C{3}!{cbhdr@fischer@C3@OH#2}
+  -[:-90]\cbhdr@C{4}!{cbhdr@fischer@C4@OH#3}
+  -[:-90]\cbhdr@C{5}!{cbhdr@fischer@C5@OH#4}
+  -[:-90]\cbhdr@C{6}(-[:0]\cbhdr@OH{6})(-[:180]H)
+  -[:-90]H
+}
+
+% pyranoses
+\cbhdr@newring\cbhdr@aldohexose@fischer@ring@pyranose#1#2#3#4#5{%
+  \cbhdr@C{1}!{cbhdr@fischer@OH#1}(-[:90]-[:0]-?)
+  -[:-90]\cbhdr@C{2}!{cbhdr@fischer@C2@OH#2}
+  -[:-90]\cbhdr@C{3}!{cbhdr@fischer@C3@OH#3}
+  -[:-90]\cbhdr@C{4}!{cbhdr@fischer@C4@OH#4}
+  -[:-90]\cbhdr@C{5}(-[:0]\cbhdr@ring@O-?)(-[:180]H)
+  -[:-90]\cbhdr@C{6}(-[:0]\cbhdr@OH{6})(-[:180]H)
+  -[:-90]H
+}
+
+% furanoses
+\cbhdr@newring\cbhdr@aldohexose@fischer@ring@furanose#1#2#3#4#5{%
+  \cbhdr@C{1}!{cbhdr@fischer@OH#1}(-[:90]-[:0]-?)
+  -[:-90]\cbhdr@C{2}!{cbhdr@fischer@C2@OH#2}
+  -[:-90]\cbhdr@C{3}!{cbhdr@fischer@C3@OH#3}
+  -[:-90]\cbhdr@C{4}(-[:0]\cbhdr@ring@O-?)(-[:180]H)
+  -[:-90]\cbhdr@C{5}!{cbhdr@fischer@C5@OH#5}
+  -[:-90]\cbhdr@C{6}(-[:0]\cbhdr@OH{6})(-[:180]H)
+  -[:-90]H
+}
+
+%%%
+% pentoses
+% chain
+\cbhdr@newchain\cbhdr@aldopentose@fischer@chain#1#2#3{%
+  \cbhdr@C{1}!{cbhdr@fischer@aldehyde}
+  -[:-90]\cbhdr@C{2}!{cbhdr@fischer@C2@OH#1}
+  -[:-90]\cbhdr@C{3}!{cbhdr@fischer@C3@OH#2}
+  -[:-90]\cbhdr@C{4}!{cbhdr@fischer@C4@OH#3}
+  -[:-90]\cbhdr@C{5}(-[:0]\cbhdr@OH{5})(-[:180]H)
+  -[:-90]H
+}
+
+% pyranoses
+\cbhdr@newring\cbhdr@aldopentose@fischer@ring@pyranose#1#2#3#4{%
+  \cbhdr@C{1}!{cbhdr@fischer@OH#1}(-[:90]-[:0]-?)
+  -[:-90]\cbhdr@C{2}!{cbhdr@fischer@C2@OH#2}
+  -[:-90]\cbhdr@C{3}!{cbhdr@fischer@C3@OH#3}
+  -[:-90]\cbhdr@C{4}!{cbhdr@fischer@C4@OH#4}
+  -[:-90]\cbhdr@C{5}(-[:0]\cbhdr@ring@O-?)(-[:180]H)
+  -[:-90]H
+}
+
+% furanoses
+\cbhdr@newring\cbhdr@aldopentose@fischer@ring@furanose#1#2#3#4{%
+  \cbhdr@C{1}!{cbhdr@fischer@OH#1}(-[:90]-[:0]-?)
+  -[:-90]\cbhdr@C{2}!{cbhdr@fischer@C2@OH#2}
+  -[:-90]\cbhdr@C{3}!{cbhdr@fischer@C3@OH#3}
+  -[:-90]\cbhdr@C{4}(-[:0]\cbhdr@ring@O-?)(-[:180]H)
+  -[:-90]\cbhdr@C{5}(-[:0]\cbhdr@OH{5})(-[:180]H)
+  -[:-90]H
+}
+
+%%%
+% tetroses
+% chain
+\cbhdr@newchain\cbhdr@aldotetrose@fischer@chain#1#2{%
+  \cbhdr@C{1}!{cbhdr@fischer@aldehyde}
+  -[:-90]\cbhdr@C{2}!{cbhdr@fischer@C2@OH#1}
+  -[:-90]\cbhdr@C{3}!{cbhdr@fischer@C3@OH#2}
+  -[:-90]\cbhdr@C{4}(-[:0]\cbhdr@OH{4})(-[:180]H)
+  -[:-90]H
+}
+
+% pyranoses
+\cbhdr@define@ring@error{fischer}{tetrose}{pyranose}
+
+% furanoses
+\cbhdr@newring\cbhdr@aldotetrose@fischer@ring@furanose#1#2#3{%
+  \cbhdr@C{1}!{cbhdr@fischer@OH#1}(-[:90]-[:0]-?)
+  -[:-90]\cbhdr@C{2}!{cbhdr@fischer@C2@OH#2}
+  -[:-90]\cbhdr@C{3}!{cbhdr@fischer@C3@OH#3}
+  -[:-90]\cbhdr@C{4}(-[:0]\cbhdr@ring@O-?)(-[:180]H)
+  -[:-90]H
+}
+
+%%%
+% trioses
+% chain
+\cbhdr@newchain\cbhdr@aldotriose@fischer@chain#1{%
+  \cbhdr@C{1}!{cbhdr@fischer@aldehyde}
+  -[:-90]\cbhdr@C{2}!{cbhdr@fischer@C2@OH#1}
+  -[:-90]\cbhdr@C{3}(-[:0]\cbhdr@OH{3})(-[:180]H)
+  -[:-90]H
+}
+
+% pyranoses
+\cbhdr@define@ring@error{fischer}{triose}{pyranose}
+
+% furanoses
+\cbhdr@define@ring@error{fischer}{triose}{furanose}
+
+% --------------------------------------------------------------------------
+% Haworth
+\newcommand*\cbhdr@decr{-} % >
+\newcommand*\cbhdr@thick{} % line width=3pt
+\newcommand*\cbhdr@incr{-} % <
+
+%%%
+% hexoses
+% chain
+\cbhdr@newchain\cbhdr@aldohexose@haworth@chain#1#2#3#4{%
+  -[:30]
+  ?(-[:90,.5]-[:150,.5]\cbhdr@HO{6})!{cbhdr@haworth@C5@OH#4}-[,,,,draw=none]
+  -[:-30,,1,,draw=none](=_[:0]\cbhdr@anomer@O)
+  \cbhdr@incr[:-150]!{cbhdr@haworth@C2@OH#1}
+  -[:-180,,,,\cbhdr@thick]!{cbhdr@haworth@C3@OH#2}
+  \cbhdr@decr[:150]?!{cbhdr@haworth@C4@OH#3}
+}
+
+% pyranoses
+\cbhdr@newring\cbhdr@aldohexose@haworth@ring@pyranose#1#2#3#4#5{%
+  -[:30]
+  ?(-[:90,.5]-[:150,.5]\cbhdr@HO{6})-\cbhdr@ring@O
+  -[:-30]!{cbhdr@haworth@OH#1}
+  \cbhdr@incr[:-150]!{cbhdr@haworth@C2@OH#2}
+  -[:-180,,,,\cbhdr@thick]!{cbhdr@haworth@C3@OH#3}
+  \cbhdr@decr[:150]?!{cbhdr@haworth@C4@OH#4}
+}
+
+% furanoses
+\cbhdr@newring\cbhdr@aldohexose@haworth@ring@furanose#1#2#3#4#5{%
+  \cbhdr@ring@O?-[:-20]!{cbhdr@haworth@OH#1}
+  -[:-110]!{cbhdr@haworth@furanose@C2@OH#2}
+  -[:180,1.1954]!{cbhdr@haworth@furanose@C3@OH#3}
+  -[:110]?!{cbhdr@haworth@furanose@C4@OH#4@C5@OH#5}
+}
+
+%%%
+% pentoses
+% chain
+\cbhdr@newchain\cbhdr@aldopentose@haworth@chain#1#2#3{%
+  ?-[:-20,,,,draw=none](=_[:0]\cbhdr@anomer@O)
+  -[:-110]!{cbhdr@haworth@furanose@C2@OH#1}
+  -[:180,1.1954]!{cbhdr@haworth@furanose@C3@OH#2}
+  -[:110]?[,,{draw=none}](-[:90,.5]-[:150,.5]\cbhdr@HO{5})
+  !{cbhdr@haworth@furanose@C4@OH#3}
+}
+
+% pyranoses
+\cbhdr@newring\cbhdr@aldopentose@haworth@ring@pyranose#1#2#3#4{%
+  -[:30]
+  ?-\cbhdr@ring@O
+  -[:-30]!{cbhdr@haworth@OH#1}
+  \cbhdr@incr[:-150]!{cbhdr@haworth@C2@OH#2}
+  -[:-180,,,,\cbhdr@thick]!{cbhdr@haworth@C3@OH#3}
+  \cbhdr@decr[:150]?!{cbhdr@haworth@C4@OH#4}
+}
+
+% furanoses
+\cbhdr@newring\cbhdr@aldopentose@haworth@ring@furanose#1#2#3#4{%
+  \cbhdr@ring@O?-[:-20]!{cbhdr@haworth@OH#1}
+  -[:-110]!{cbhdr@haworth@furanose@C2@OH#2}
+  -[:180,1.1954]!{cbhdr@haworth@furanose@C3@OH#3}
+  -[:110]?(-[:90,.5]-[:150,.5]\cbhdr@HO{5})
+}
+
+%%%
+% tetroses
+% chain
+\cbhdr@define@chain@error{haworth}{tetrose}
+
+% pyranoses
+\cbhdr@define@ring@error{haworth}{tetrose}{pyranose}
+
+% furanoses
+\cbhdr@newring\cbhdr@aldotetrose@haworth@ring@furanose#1#2#3{%
+  \cbhdr@ring@O?-[:-20]!{cbhdr@haworth@OH#1}
+  -[:-110]!{cbhdr@haworth@furanose@C2@OH#2}
+  -[:180,1.1954]!{cbhdr@haworth@furanose@C3@OH#3}
+  -[:110]?
+}
+
+%%%
+% trioses
+% chain
+\cbhdr@define@chain@error{haworth}{triose}
+
+% pyranoses
+\cbhdr@define@ring@error{haworth}{triose}{pyranose}
+
+% furanoses
+\cbhdr@define@ring@error{haworth}{triose}{furanose}
+
+% --------------------------------------------------------------------------
+% Chair
+
+%%%
+% hexoses
+% chain
+\cbhdr@newchain\cbhdr@aldohexose@chair@chain#1#2#3#4{%
+  -[:-10]
+  ?(-[:150,.75]-[:90,.5,,1]\cbhdr@OH{6})!{cbhdr@chair@C5@OH#4}-[:10,,,,draw=none]
+  -[:-50,,1,,draw=none](=_[:70]\cbhdr@anomer@O)
+  \cbhdr@incr[:-170]!{cbhdr@chair@C2@OH#1}
+  -[:-190,,,,\cbhdr@thick]!{cbhdr@chair@C3@OH#2}
+  \cbhdr@decr[:130]?!{cbhdr@chair@C4@OH#3}
+}
+
+% pyranoses
+\cbhdr@newring\cbhdr@aldohexose@chair@ring@pyranose#1#2#3#4#5{%
+  -[:-10]
+  ?(-[:150,.75]-[:90,.5,,1]\cbhdr@OH{6})-[:10]\cbhdr@ring@O
+  -[:-50]!{cbhdr@chair@OH#1}
+  \cbhdr@incr[:170]!{cbhdr@chair@C2@OH#2}
+  -[:190,,,,\cbhdr@thick]!{cbhdr@chair@C3@OH#3}
+  \cbhdr@decr[:130]?!{cbhdr@chair@C4@OH#4}
+}
+
+% furanoses
+\newrobustcmd*\cbhdr@aldohexose@chair@ring@furanose{%
+  \cbhdr@chair@error{furanose rings}%
+}
+
+%%%
+% pentoses
+\cbhdr@define@chair@errors{pentose}
+
+%%%
+% tetroses
+\cbhdr@define@chair@errors{tetrose}
+
+%%%
+% trioses
+\cbhdr@define@chair@errors{triose}
+
+
+% ==========================================================================
+% the user commands - built from the commands above using the already
+% mentioned naming scheme
+%
+% <module>@<model>@<chain>/<ring>(@<ringtype>)
+
+\newcommand*\cbhdr@model{}    % fischer/haworth/chair
+\newcommand*\cbhdr@fischer{}  % @skeleton
+\newcommand*\cbhdr@form{}     % chain/ring
+\newcommand*\cbhdr@chain{chain}
+\newcommand*\cbhdr@ring{ring@\cbhdr@ringtype}
+\newcommand*\cbhdr@ringtype{} % pyranose/furanose
+\newcommand*\cbhdr@ringtype@default{}
+
+% --------------------------------------------------------------------------
+% options for the user command:
+\pgfkeys{
+  cbhdr/.cd,
+    model/.is choice ,
+    model/fischer/.is choice ,
+    model/fischer/skeleton/.code = \def\cbhdr@model{fischer@skeleton} ,
+    model/fischer/full/.code     = \def\cbhdr@model{fischer} ,
+    model/fischer/.default       = full ,
+    model/haworth/.code          = \def\cbhdr@model{haworth} ,
+    model/chair/.code            = \def\cbhdr@model{chair} ,
+    chain/.code                  = \def\cbhdr@constitution{chain} ,
+    ring/.is choice ,
+    ring/true/.code              = \def\cbhdr@constitution{ring@\cbhdr@ringtype@default} ,
+    ring/pyranose/.code          = \def\cbhdr@constitution{ring@pyranose} ,
+    ring/furanose/.code          = \def\cbhdr@constitution{ring@furanose} ,
+    ring/.default                = true ,
+    anomer/.is choice ,
+    anomer/alpha/.code           = \def\cbhdr@anomer{alpha} ,
+    anomer/beta/.code            = \def\cbhdr@anomer{beta} ,
+    anomer/undetermined/.code    = \def\cbhdr@anomer{undetermined} ,
+    length/.is choice ,
+    length/6/.code               =
+      \def\cbhdr@ringtype@default{pyranose}
+      \def\cbhdr@length{aldohexose} ,
+    length/5/.code               =
+      \def\cbhdr@ringtype@default{furanose}
+      \def\cbhdr@length{aldopentose} ,
+    length/4/.code               =
+      \def\cbhdr@ringtype@default{furanose}
+      \def\cbhdr@length{aldotetrose} ,
+    length/3/.code               =
+      % doesn't matter: will cause an error anyway
+      \def\cbhdr@ringtype@default{pyranose}
+      \def\cbhdr@length{aldotriose} ,
+    hexose/.style                = { length=6 } ,
+    pentose/.style               = { length=5 } ,
+    tetrose/.style               = { length=4 } ,
+    triose/.style                = { length=3 } ,
+    3d/.is choice ,
+    3d/true/.code                =
+      \def\cbhdr@decr{>}
+      \def\cbhdr@thick{line width=3pt}
+      \def\cbhdr@incr{<} ,
+    3d/false/.code               =
+      \def\cbhdr@decr{-}
+      \def\cbhdr@thick{}
+      \def\cbhdr@incr{-} ,
+    3d/.default                  = true ,
+    defaults/.style              = {
+      model  = fischer ,
+      chain ,
+      anomer = alpha ,
+      length = 6
+    } ,
+    color/.code 2 args = \cbhdr@defcolor{#1}{#2}
+}
+\pgfqkeys{/cbhdr}{defaults}
+
+% --------------------------------------------------------------------------
+% the user command:
+\newrobustcmd*\cbhdr@carbohydrate[2]{%
+  \begingroup
+    \pgfqkeys{/cbhdr}{defaults,#1}%
+    \csuse{cbhdr@\cbhdr@length @\cbhdr@model @\cbhdr@constitution}{#2}%
+  \endgroup
+}
+
+\newrobustcmd*\carbohydrate[2][]{\cbhdr@carbohydrate{#1}{#2}}
+
+% ==========================================================================
+% a command to define ready made carbohydrates
+
+\newrobustcmd*\newaldose[1]{%
+  \@ifnextchar[ % ]
+    {\cbhdr@newaldose{#1}}
+    {\cbhdr@newaldose{#1}[]}%
+}
+
+\protected\def\cbhdr@newaldose#1[#2]#3{%
+  \cbhdr@expand@x
+  \pgfkeys{
+    cbhdr/.cd,
+      \cbhdr@stripbs#1-defaults/.style={\unexpanded{#2}}
+  }%
+  \newrobustcmd*#1[1][]{%
+    \expandafter\cbhdr@carbohydrate\expandafter{\cbhdr@stripbs#1-defaults,##1}{#3}%
+  }%
+}
+
+\newrobustcmd*\renewaldose[1]{%
+  \@ifnextchar[ % ]
+    {\cbhdr@renewaldose{#1}}
+    {\cbhdr@renewaldose{#1}[]}%
+}
+
+\protected\def\cbhdr@renewaldose#1[#2]#3{%
+  \cbhdr@expand@x
+  \pgfkeys{
+    cbhdr/.cd,
+      \cbhdr@stripbs#1-defaults/.style={\unexpanded{#2}}
+  }%
+  \renewrobustcmd*#1[1][]{%
+    \expandafter\cbhdr@carbohydrate\expandafter{\cbhdr@stripbs#1-defaults,##1}{#3}%
+  }%
+}
+
+% ==========================================================================
+% predefined carbohydrates:
+% aldohexoses:
+\newaldose \allose   [hexose]{rrrr}
+\newaldose \altrose  [hexose]{lrrr}
+\newaldose \glucose  [hexose]{rlrr}
+\newaldose \gulose   [hexose]{rrlr}
+\newaldose \mannose  [hexose]{llrr}
+\newaldose \idose    [hexose]{lrlr}
+\newaldose \galactose[hexose]{rllr}
+\newaldose \talose   [hexose]{lllr}
+
+% aldopentoses:
+\newaldose \ribose   [pentose]{rrr}
+\newaldose \arabinose[pentose]{lrr}
+\newaldose \xylose   [pentose]{rlr}
+\newaldose \lyxose   [pentose]{llr}
+
+\newaldose \desoxyribose[pentose]{0rr}
+
+% aldotetroses:
+\newaldose \erythrose[tetrose]{rr}
+\newaldose \threose  [tetrose]{lr}
+
+% aldotrioses:
+\newaldose \glycerinaldehyde[triose]{r}
+
+% ==========================================================================
+% setup commands
+% general defaults:
+\newrobustcmd*\setcarbohydrates[1]{%
+  \pgfkeys{
+    cbhdr/.cd ,
+      defaults/.style = {#1} ,
+      defaults
+  }%
+}
+
+% defaults for particular carbohydrate defined with \newaldose:
+\newrobustcmd*\setcarbohydratedefaults[2]{%
+  \edef\cbhdr@tmpa{\cbhdr@stripbs#1}%
+  \pgfkeys{
+    cbhdr/.cd ,
+      \cbhdr@tmpa-defaults/.style = { #2 } ,
+      \cbhdr@tmpa-defaults
+  }%
+}
+
+\endinput
+% ==========================================================================
+% HISTORY:
+
+% ==========================================================================
+% TODO:
+- Ringe fuer L-Saccharide
+- Ketten für Tri- Tetr- und Pentosen
+- Optionen für Farben
+
+- Ketosen - viell. nur Fructose
+
+- Optionen für oxidierte u reduzierte Formen?
+