<html><head><meta name="color-scheme" content="light dark"></head><body><pre style="word-wrap: break-word; white-space: pre-wrap;">%% MSC Macro Package
%% msc.sty
%%
%% Copyright 2022 V. Bos, T. van Deursen, P. Kordy,  and S. Mauw
%
% 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 P. Kordy
%
% This program consists of the files
%   msc.sty
%   manual.tex
%   manual_macros.tex
%   biblio.bib
%   README
%   COPYRIGHT

% Contact address:
% Reynaldo Gil Pons
% UniversitĂŠ du Luxembourg 
% Maison du Nombre
% 6 Av. de la Fonte
% L-4364 Esch-sur-Alzette
% Email: reynaldo.gilpons@uni.lu
% Website: http://satoss.uni.lu/mscpackage/

\def\mscdate{2022/05/13}% update this whenever this file changes
\def\mscversion{2.00}%   update this whenever a new version is ready
\NeedsTeXFormat{LaTeX2e}[1999/12/01]
\ProvidesPackage{msc}[\mscdate, v\mscversion]
\typeout{msc version \mscversion. (\mscdate)}
\RequirePackage{tikz,xstring,calc}
\usetikzlibrary{
  positioning,
  fit,
  calc,
  arrows,
  decorations.markings,
  shapes.misc,
  shapes.geometric,
  shapes.symbols
}
\pgfdeclarelayer{background} %background for drawing grid
\pgfsetlayers{background,main}


% {string}{target1}{target2}{code for match}{code for no match}
\newcommand*{\msc@StrEqEither}[5]{
    \IfEqCase{#1}{{#2}{#4}{#3}{#4}}[#5]
}
\newcommand*{\msc@caseFiveEither}[8]{
    \IfEqCase{#1}{{#2}{#7}{#3}{#7}{#4}{#7}{#5}{#7}{#6}{#7}}[#8]
}
%\newlength{\msc@textheight}
%\newlength{\msc@textdepth}
%\newlength{\msc@textwidth}
\newsavebox{\msc@box}
\newcommand{\msc@savebox}[1]{
  \savebox{\msc@box}{\pgfinterruptpicture#1\endpgfinterruptpicture}
}
%
%% \tracingmacros=2 \tracingcommands=2 %used for debugging
% "msc" is a family
\pgfkeys{/msc/.is family}
% set up a search path:
\pgfkeys{/msc/.search also={/tikz}}
% \pgfkeys{/msc/message/.search also={/msc}}
\newif\ifmsc@isstar
\newif\ifmsc@ismessreplay
\def\mscset{\pgfqkeys{/msc}}
\def\mscget#1{\pgfkeysvalueof{/msc/#1}}
%  * Arrow *
\pgfarrowsdeclare{mscarrow}{mscarrow}
{
  \pgfmathparse{\pgfgetarrowoptions{mscarrow}}%
  \ifpgfmathunitsdeclared%
    \pgfmathparse{\pgfmathresult pt}%
  \else%
    \pgfmathparse{\pgfmathresult*\pgflinewidth}%
  \fi%
  \let\thickness=\pgfmathresult
%   \edef\msc@thickness=\pgfmathresult
  \pgfutil@tempdima=0.28pt%
  \pgfutil@tempdimb=\pgfmathresult pt
  \ifdim\pgfinnerlinewidth&gt;0pt%
    \pgfmathsetlength\pgfutil@tempdimb{.6\pgfutil@tempdimb-.4*\pgfinnerlinewidth}%
  \fi%
  \advance\pgfutil@tempdima by.3\pgfutil@tempdimb%
  \pgfarrowsleftextend{-3\pgfutil@tempdima}
  \pgfarrowsrightextend{+5\pgfutil@tempdima}
}
{
  \pgfmathparse{\pgfgetarrowoptions{mscarrow}}%
  \ifpgfmathunitsdeclared%
    \pgfmathparse{\pgfmathresult pt}%
  \else%
    \pgfmathparse{\pgfmathresult*\pgflinewidth}%
  \fi%
  \let\thickness=\pgfmathresult
  \pgfsetlinewidth{\thickness pt}
  \pgfutil@tempdima=0.28pt%
  \pgfutil@tempdimb=\pgflinewidth%
  \ifdim\pgfinnerlinewidth&gt;0pt%
    \pgfmathsetlength\pgfutil@tempdimb{.6\pgflinewidth-.4*\pgfinnerlinewidth}%
  \fi%
  \advance\pgfutil@tempdima by.3\pgfutil@tempdimb%
  \pgfpathmoveto{\pgfqpoint{5\pgfutil@tempdima}{0pt}}
  \pgfpathlineto{\pgfqpoint{-3\pgfutil@tempdima}{4\pgfutil@tempdima}}
  \pgfpathlineto{\pgfpointorigin}
  \pgfpathlineto{\pgfqpoint{-3\pgfutil@tempdima}{-4\pgfutil@tempdima}}
  \pgfusepathqfill
}
\newlength{\actionheight}               % height of action symbols
\newlength{\actionwidth}                % width of action symbol
\newlength{\bottomfootdist}             % distance between bottom of foot symbol and frame
\newlength{\msccommentdist}             % distance of comment to its instance
\newlength{\conditionheight}            % height of condition symbols
\newlength{\conditionoverlap}           % overlap of condition symbol
\newlength{\envinstdist}                % distance between environments and nearest instance line
\newlength{\firstlevelheight}           % height of level just below head symbols
\newlength{\gatesymbolradius}           % radius of the gate symbol
\newlength{\hmscconditionheight}        % height of hmsc condition symbol
\newlength{\hmscconditionwidth}         % width of hmsc condition symbol
\newlength{\hmscconnectionradius}       % radius of hmsc connection symbols
\newlength{\hmscreferenceheight}        % % height of hmsc and mscdoc reference symbol
\newlength{\hmscreferencewidth}         % width of hmsc and mscdoc reference symbol
\newlength{\hmscstartsymbolwidth}       % width of hmsc start/end symbol
\newlength{\inlineoverlap}              % overlap of inline symbol
\newlength{\instbarwidth}               % default width of vertical instance bars
\newlength{\instdist}                   % distance between (vertical) instance lines
\newlength{\instfootheight}             % height of foot symbols
\newlength{\instheadheight}             % height of head symbols
\newlength{\instwidth}                  % width of header and foot symbols
\newlength{\labeldist}                  % distance between labels and message lines or head symbol boxes
\newlength{\lastlevelheight}            % height of level just above foot symbols
\newlength{\leftnamedist}               % distance between left of frame and (top of) msc title
\newlength{\levelheight}                % height of a level
\newlength{\lostsymbolradius}           % radius of the lost and found symbols
\newlength{\markdist}                   % distance between mark and its instance
\newlength{\measuredist}                % user definable length for horizontal measure distance
\newlength{\measuresymbolwidth}         % width of measure symbols
\newlength{\mscdocreferenceheight}      % minimal height of mscdoc reference
\newlength{\mscdocreferencewidth}       % minimal width of mscdoc reference
\newlength{\referenceoverlap}           % overlap of reference symbol
\newlength{\regionbarwidth}             % the width of the coregion start and end symbol
\newlength{\selfmesswidth}              % length of horizontal arms of self messages
\newlength{\stopwidth}                  % width of the stop symbol
\newlength{\timerwidth}                 % width of the timer symbols
\newlength{\topheaddist}                % distance between top of head symbols and frame
\newlength{\topnamedist}                % distance between top of frame and (top of) msc title
\mscset{%
  %mscdoc keys
  /msc/mscdoc margin/.code={
    \mscset{
      north mscdoc margin/.initial=#1,
      south mscdoc margin/.initial=#1,
      east mscdoc margin/.initial=#1,
      west mscdoc margin/.initial=#1
     }
  },
  top mscdoc margin/.style={north mscdoc margin=#1},
  bottom mscdoc margin/.style={south mscdoc margin=#1},
  left mscdoc margin/.style={west mscdoc margin=#1},
  right mscdoc margin/.style={east mscdoc margin=#1},
  /msc/mscdoc margin=0.5cm,
  /msc/mscdoc keyword/.initial=mscdoc,
  %hmsc keys
  /msc/hmsc keyword/.initial=hmsc,
  /msc/hmsc margin/.code={
    \mscset{
      north hmsc margin/.initial=#1,
      south hmsc margin/.initial=#1,
      east hmsc margin/.initial=#1,
      west hmsc margin/.initial=#1
     }
  },
  top hmsc margin/.style={north hmsc margin=#1},
  bottom hmsc margin/.style={south hmsc margin=#1},
  left hmsc margin/.style={west hmsc margin=#1},
  right hmsc margin/.style={east hmsc margin=#1},
  /msc/hmsc margin=0.5cm,
  %msc keys
  /msc/msc keyword/.initial=msc,
  /msc/inline overlap/.code={
    \mscset{
      right inline overlap/.initial=#1,
      left inline overlap/.initial=#1
     }
  },
  environment distance/.code={
    \mscset{
      right environment distance/.initial=#1,
      left environment distance/.initial=#1
     }
  },                                                 % distance between environments and the % first level
  /msc/reference overlap/.code={
    \mscset{
      right reference overlap/.initial=#1,
      left reference overlap/.initial=#1
     }
  },
  /msc/message options/.is family,     %options for message
  /msc/action options/.is family,      %options for action and naction
  /msc/msccomment options/.is family,  %options for message comments
% Default value keys
  /msc/line width/.initial=0.7pt,
  side/.initial=left,                  %side on which to draw self message
  position/.initial=above,             %how to draw mscmark - possible %values:above mid below 
  /msc/side/.belongs to family=/msc/message options,
  /msc/side/.belongs to family=/msc/msccomment options,
  /msc/msccomment distance/.belongs to family=/msc/msccomment options,
  /msc/offset/.belongs to family=/msc/msccomment options,
  /msc/offset/.belongs to family=/msc/message options,
  /msc/timer width/.belongs to family=/msc/msccomment options,
  /msc/self message width/.belongs to family=/msc/msccomment options,
  /msc/label distance/.belongs to family=/msc/msccomment options,
  /msc/label position/.initial=above, %position of label in self message
  /msc/label position/.belongs to family=/msc/message options,
  /msc/level shift/.initial=0,        %level shift in message
  /msc/offset/.initial=2,             %level shift in timers/self message etc
  /msc/dummy text/.initial={ },       %text used for determining the size of dummy node
  /msc/level shift/.belongs to family=/msc/message options,
  /msc/pos/.initial=0.5,              %placement of label in message
  /msc/pos/.belongs to family=/msc/message options,
  level offset/.initial=1,            %level shift in nextlevel
  level offset/.default=1,            
  /tikz/font=\small,
  /msc/draw frame/.initial=,       %color of the frame - if "none" we do not draw - "empty" uses last color usually black
  /msc/draw frame/.default=,       
  /msc/draw head/.initial=,       %color of the instance head
  /msc/draw head/.default=,       
  /msc/draw foot/.initial=,       %color of the instance foot
  /msc/draw foot/.default=,       
  /msc/draw grid/.initial=none,       %style to draw help lines - if empty we do
                                %not draw, other possible values are "none", "grid" or "color grid"
  /msc/draw grid/.default=grid,       
  /msc/draw color grid/.style={draw grid=color grid},       
% the lengths
  fat/.initial=normal,
  fat/.default=fat,
  %sizes
  /tikz/font=\normalsize,                            % use normal size of font
  action height/.initial=\the\actionheight,          % height of action symbols
  action height/.code={\setlength{\actionheight}{#1}},
  action width/.initial=\the\actionwidth,            % width of action symbol
  action width/.code={\setlength{\actionwidth}{#1}},
  foot distance/.initial=\the\bottomfootdist,        % distance between bottom of foot symbol and frame
  foot distance/.code={\setlength{\bottomfootdist}{#1}},
  msccomment distance/.initial=\the\msccommentdist,  % distance of comment to its instance
  msccomment distance/.code={\setlength{\msccommentdist}{#1}},     % distance of comment to its instance
  condition height/.initial=\the\conditionheight,    % height of condition symbols
  condition height/.code={\setlength{\conditionheight}{#1}},        % height of condition symbols
  condition overlap/.initial=\the\conditionoverlap,  % overlap of condition symbol
  condition overlap/.code={\setlength{\conditionoverlap}{#1}},       % overlap of condition symbol
  first level height/.initial=\the\firstlevelheight, % height of level just below head symbols
  first level height/.code={\setlength{\firstlevelheight}{#1}},
  gate symbol radius/.initial=\the\gatesymbolradius, % radius of the gate symbol
  gate symbol radius/.code={\setlength{\gatesymbolradius}{#1}},
  hmsc condition height/.initial=\the\hmscconditionheight,   % height of hmsc condition symbol
  hmsc condition height/.code={\setlength{\hmscconditionheight}{#1}},
  hmsc condition width/.initial=\the\hmscconditionwidth,     % width of hmsc condition symbol
  hmsc condition width/.code={\setlength{\hmscconditionwidth}{#1}},
  hmsc connection radius/.initial=\the\hmscconnectionradius, % radius of hmsc connection symbols
  hmsc connection radius/.code={\setlength{\hmscconnectionradius}{#1}},
  reference height/.initial=\the\hmscreferenceheight,        % height of hmsc and mscdoc reference symbol
  reference height/.code={\setlength{\hmscreferenceheight}{#1}},
  reference width/.initial=\the\hmscreferencewidth,          % width of hmsc and mscdoc reference symbol
  reference width/.code={\setlength{\hmscreferencewidth}{#1}},        % width of hmsc and mscdoc reference symbol
  hmsc symbol width/.initial=\the\hmscstartsymbolwidth,     % width of hmsc start/end symbol
  hmsc symbol width/.code={\setlength{\hmscstartsymbolwidth}{#1}},  % width of hmsc start/end symbol
  instance distance/.initial=\the\instdist,                 % distance between (vertical) instance lines
  instance distance/.code={\setlength{\instdist}{#1}},
  foot height/.initial=\the\instfootheight,                 % height of foot symbols
  foot height/.code={\setlength{\instfootheight}{#1}},
  head height/.initial=\the\instheadheight,                 % height of head symbols
  head height/.code={\setlength{\instheadheight}{#1}},
  instance width/.initial=\the\instwidth,                   % width of header and foot symbols
  instance width/.code={\setlength{\instwidth}{#1}},
  label distance/.initial=\the\labeldist,                   % distance between labels and message lines or head symbol boxes
  label distance/.code={\setlength{\labeldist}{#1}},
  last level height/.initial=\the\lastlevelheight,          % height of level just above foot symbols
  last level height/.code={\setlength{\lastlevelheight}{#1}},
  title distance/.initial=\the\leftnamedist,                % distance between left of frame and (top of) msc title
  title distance/.code={\setlength{\leftnamedist}{#1}},
  level height/.initial=\the\levelheight,                   % height of a level
  level height/.code={\setlength{\levelheight}{#1}},
  lost symbol radius/.initial=\the\lostsymbolradius,        % radius of the lost and found symbols
  lost symbol radius/.code={\setlength{\lostsymbolradius}{#1}},
  mark distance/.initial=\the\markdist,                     % distance between mark and its instance
  mark distance/.code={\setlength{\markdist}{#1}},
  measure distance/.initial=\the\measuredist,               % user definable length for horizontal measure distance
  measure distance/.code={\setlength{\measuredist}{#1}},
  measure symbol width/.initial=\the\measuresymbolwidth,    % width of measure symbols
  measure symbol width/.code={\setlength{\measuresymbolwidth}{#1}},
%   reference overlap/.initial=\the\referenceoverlap,         % overlap of reference symbol
%   reference overlap/.code={\setlength{\referenceoverlap}{#1}},
  region width/.initial=\the\regionbarwidth,           % the width of the coregion start and end symbol
  region width/.code={\setlength{\regionbarwidth}{#1}},
%   region width/.initial=0.4cm,                             % the width of the activation, suspension and coregion rectangle
  self message width/.initial=\the\selfmesswidth,          % length of horizontal arms of self messages
  self message width/.code={\setlength{\selfmesswidth}{#1}},
  stop width/.initial=\the\stopwidth,                      % width of the stop symbol
  stop width/.code={\setlength{\stopwidth}{#1}},
  timer width/.initial=\the\timerwidth,                    % width of the timer symbols
  timer width/.code={\setlength{\timerwidth}{#1}},
  head top distance/.initial=\the\topheaddist,             % distance between top of head symbols and frame
  head top distance/.code={\setlength{\topheaddist}{#1}},
  title top distance/.initial=\the\topnamedist,            % distance between top of frame and (top of) msc title
  title top distance/.code={\setlength{\topnamedist}{#1}},
  instance end/.initial=stop,                              % type of ending for the instance foot (foot or stop) - changed to follow ITU-T Z.120
  title position/.initial=left,                            % justification of the title: left, right or center
  arrow scale/.initial=1.5,                                % scale for the
                                % arrows
  msc scale/.initial=1,                                    % sets the scale factor
  msc scale/.code={                                        % that scales everynthing including text but one must be
    \pgfutil@ifundefined{msc@tikzstarted}{\relax}{         % careful with rotation transformations
      \mscset{
      /tikz/scale=#1,
      /tikz/every node/.style={scale=#1}}
    }
   \mscset{msc scale/.initial=#1}
  },
%Styles
  every instance head/.style={},             % style applied to all instance heads
  every instance foot/.style={},             % style applied to all instance feet
  every instance line/.style={},             % style applied to all instance lines
  every message/.style={},                   % style applied to all message arrows
  every msccomment/.style={},                % style applied to all msccomments
  every mscmark/.style={},                   % style applied to all mscmarks
  every action/.style={},                    % style applied to all actions and nactions
  every action node/.style={},               % style applied to all actions and nactions nodes
  every region/.style={},                    % style applied to all regions
  every coregion/.style={},                  % style applied to all coregions
  every suspension/.style={},                % style applied to all suspension regions
  every activation/.style={},                % style applied to all activation regions
  every timer/.style={},                     % style applied to simple timers
  every measure/.style={},                   % style applied to all measures
  every lostfound/.style={},                 % style applied to all lost and found messages
  every condition/.style={},                 % style applied to all conditions
  every order/.style={},                     % style applied to all orders
  every reference/.style={},                 % style applied to all references
  every inline/.style={},                    % style applied to all inline expressions
  large values/.style={%
    /tikz/font=\normalsize,
    /tikz/line width=0.8pt,
    /msc/line width=0.8pt,
    action height=0.75cm,
    /msc/action height/.belongs to family=/msc/action options,
    action width=1.25cm,
    /msc/action width/.belongs to family=/msc/action options,
    foot distance=1cm,
    msccomment distance=1.5cm,
    condition height=0.75cm,
    condition overlap=0.6cm,
    environment distance=2.5cm,
    first level height=0.75cm,
    gate symbol radius=0.5mm,
    hmsc condition height=0.8cm,
    hmsc condition width=1.6cm,
    hmsc connection radius=0.06cm,
    reference height=0.8cm,
    reference width=1.6cm,
    hmsc symbol width=0.85cm,
    inline overlap=1.5cm,
    instance distance=1.25cm,
    foot height=0.25cm,
    head height=0.6cm,
    instance width=1.75cm,
    label distance=1ex,
    last level height=0.5cm,
    title distance=0.3cm,
    level height=0.75cm,
    lost symbol radius=0.15cm,
    mark distance=1cm,
    measure distance=0.75cm,
    measure symbol width=0.25cm,
    reference overlap=1.5cm,
    region width=0.5cm,
    self message width=0.75cm,
    stop width=0.6cm,
    timer width=0.4cm,
    head top distance=1.5cm,
    title top distance=0.3cm,
    arrow scale=2
   },
  normal values/.style={%
%     /tikz/font=\small,%
    /tikz/line width=0.7pt,
    /msc/line width=0.7pt,
    action height=0.6cm,
    action width=1.25cm,
    foot distance=0.7cm,
    msccomment distance=1.1cm,
    condition height=0.6cm,
    condition overlap=0.5cm,
    environment distance=2cm,
    first level height=0.6cm,
    gate symbol radius=0.5mm,
    hmsc condition height=0.7cm,
    hmsc condition width=1.4cm,
    hmsc connection radius=0.05cm,
    reference height=0.7cm,
    reference width=1.4cm,
    hmsc symbol width=0.7cm,
    inline overlap=1cm,
    instance distance=0.6cm,
    foot height=0.2cm,
    head height=0.55cm,
    instance width=1.6cm,
    label distance=1ex,
    last level height=0.4cm,
    title distance=0.2cm,
    level height=0.5cm,
    lost symbol radius=0.12cm,
    mark distance=1cm,
    measure distance=0.6cm,
    measure symbol width=0.2cm,
    reference overlap=1cm,
    region width=0.4cm,
    self message width=0.6cm,
    stop width=0.5cm,
    timer width=0.3cm,
    head top distance=1.3cm,
    title top distance=0.2cm,
    arrow scale=1.5
  },
  small values/.style={%
    /tikz/font=\small,%
    /tikz/line width=0.6pt,
    /msc/line width=0.6pt,
    action height=0.5cm,
    action width=1.2cm,
    foot distance=0.5cm,
    msccomment distance=0.75cm,
    condition height=0.5cm,
    condition overlap=0.4cm,
    environment distance=1.2cm,
    first level height=0.4cm,
    gate symbol radius=0.5mm,
    hmsc condition height=0.6cm,
    hmsc condition width=1.2cm,
    hmsc connection radius=0.04cm,
    reference height=0.6cm,
    reference width=1.2cm,
    hmsc symbol width=0.4cm,
    inline overlap=0.75cm,
    instance distance=0.3cm,
    foot height=0.15cm,
    head height=0.5cm,
    instance width=1.2cm,
    label distance=0.8ex,
    last level height=0.3cm,
    title distance=0.1cm,
    level height=0.4cm,
    lost symbol radius=0.08cm,
    mark distance=0.4cm,
    measure distance=0.4cm,
    measure symbol width=0.15cm,
    reference overlap=0.75cm,
    region width=0.2cm,
    self message width=0.4cm,
    stop width=0.3cm,
    timer width=0.2cm,
    head top distance=1.2cm,
    title top distance=0.1cm,
    arrow scale=1.2
  },
  /msc/start symbol/.style={draw,/tikz/line width=\mscget{line width},
    inner sep=0,
    isosceles triangle,isosceles triangle apex angle=60,
    shape border rotate=-90,minimum width=\mscget{hmsc symbol width}},
    /msc/end symbol/.style={start symbol,shape border rotate=90},
%style to %draw hmsc condition
  /msc/condition/.style={draw,/tikz/line width=\mscget{line width},
    minimum width=\mscget{hmsc condition width},
    minimum height=\mscget{hmsc condition height},
    inner sep=0pt,
    signal pointer angle=120,
    signal to=east and west,
    signal},
  /msc/connection/.style={draw,/tikz/line width=\mscget{line width},
    minimum width=2*(\mscget{hmsc connection radius}) + \mscget{line width},
    circle
  },
  /msc/reference/.style={draw,/tikz/line width=\mscget{line width},
    minimum width=\mscget{reference width},
    minimum height=\mscget{reference height},
    inner sep=2pt,
    rounded corners=0.125cm,
    rectangle,
  },
  mscdash/.style={%
    dash pattern=on 4pt off 4pt
  },
  suspension dash/.style={%
    dash pattern=on 7pt off 7pt,
    dash phase=3.5pt
  },
  settimer style/.style={%
    /tikz/line width=\mscget{line width}, draw,
    to path={-- ++(60:#1) -- ++(-#1,0) -- ++(-60:2*#1) -- ++(-#1,0) -- ++(60:#1)  -- (\tikztotarget)}
  },
  timeout style/.style={%
    settimer style={#1}, arrow style
  },
  stoptimer style/.style={%
    /tikz/line width=\mscget{line width}, draw,
    to path={ ++(0.5*#1,0.5*#1) -- ++(-#1,-#1) ++(0,#1) -- ++(#1,-#1) ++(-0.5*#1,0.5*#1) -- (\tikztotarget)}
  },
  set mscarrow thickness/.code={
     \pgfsetarrowoptions{mscarrow}{#1}},
  arrow style/.default=\mscget{arrow scale}*\mscget{line width},
  arrow style/.style={set mscarrow thickness=#1,
    shorten &gt;=\mscget{line width}/2,
    -mscarrow
  },
  instance head/.style={%
    rectangle,
    text height=1.5ex,%
    inner sep=2pt,
%     text width=\mscget{instance width}, text centered,%uncomment to get old behaviour
%     transform shape,
    /tikz/line width=\mscget{line width},
    minimum height=\mscget{head height},%
    minimum width=\mscget{instance width},%
    label={[text height=1.5ex,text depth=0ex,
      inner sep=0pt, /tikz/label distance=\mscget{label
        distance}-\mscget{line width}-0.1ex]above:#1}%
  },
  replay/.style={%
    /tikz/line width=\mscget{line width},
    line cap=butt,
    mscdash
  },
  msccomment/.style={%
    /tikz/line width=\mscget{line width},
    line cap=round,
  },
  msccomment line/.style={%
    mscdash
  },
  message/.style={%
    /tikz/line width=\mscget{line width},
    arrow style,
    line cap=round,
  },
  %action/.style={%
    %/tikz/line width=\mscget{line width},
    %line cap=round,
  %},
  instance line/.style={%
    /tikz/line width=\mscget{line width},
    draw,%orange
%     line cap=round
  },
  message loop/.default=\mscget{self message width},
  message loop/.style={%
    to path={-- ++(#1,0) coordinate (msc@somepoint) -- (msc@somepoint |-
      \tikztotarget) \tikztonodes -- (\tikztotarget)}
  },
  order loop/.default=\mscget{self message width},
  order loop/.style={%
    set mscarrow thickness=\mscget{arrow scale}*\mscget{line width},
    decoration={markings, mark=at position \mscget{pos} with {\arrow{mscarrow}}},
    /tikz/line width=\mscget{line width},postaction={decorate},
    line cap=round,
    mscdash,
    to path={-- ++(#1,0) coordinate (msc@somepoint) -- (msc@somepoint |-
      \tikztotarget) \tikztonodes -- (\tikztotarget)}
  },
  order/.style={%
    set mscarrow thickness=\mscget{arrow scale}*\mscget{line width},
    decoration={markings, mark=at position \mscget{pos} with {\arrow{mscarrow}}},
    /tikz/line width=\mscget{line width},postaction={decorate},
    line cap=round,
    mscdash,
  },
  settimeout style/.default={\mscget{self message width}}{\mscget{timer width}},
  settimeout style/.style 2 args={/msc,
    /tikz/line width=\mscget{line width}, draw, arrow style,
    to path={-- ++(#1,0) coordinate (msc@somepoint) -- ++(60:#2) --
      ++(-#2,0)--++(-60:2*#2) coordinate (msc@somepoin) -- ++(-#2,0) --(msc@somepoint)
      ($ (msc@somepoint)!0.866*#2!(\tikztotarget-|msc@somepoint) $) --
      (\tikztotarget-|msc@somepoint) -&gt; (\tikztotarget)
    }
  },
  setstoptimer style/.default={\mscget{self message width}}{\mscget{timer width}},
  setstoptimer style/.style 2 args={/msc,
    /tikz/line width=\mscget{line width}, draw,
    to path={-- ++(#1,0) coordinate (msc@somepoint) -- ++(60:#2) --
      ++(-#2,0)--++(-60:2*#2) coordinate (msc@somepoin) -- ++(-#2,0) --(msc@somepoint)
      ($ (msc@somepoint)!0.866*#2!(\tikztotarget-|msc@somepoint) $) --
      (\tikztotarget-|msc@somepoint) ++(0.5*#2,0.5*#2) -- ++(-#2,-#2)
      ++(0,#2) -- ++(#2,-#2) ++(-0.5*#2,0.5*#2) --
      (\tikztotarget)
  }},
  measure style/.default={\mscget{measure distance}}{\mscget{measure symbol width}},
  measure style/.style 2 args={%
    /tikz/line width=\mscget{line width}, mscdash,
    to path={-- ++(#1,0) coordinate (a)
      ($ (a)!0.866*#2!(\tikztotarget-|a)$) -- ($(\tikztotarget-|a) !0.866*#2!(a) $)
      (a|-\tikztotarget) \tikztonodes coordinate (b) -- (\tikztotarget)
      \pgfextra{ \path[draw,/msc/mscdash,/tikz/line width=\mscget{line width}];}
      (a)--($ (a)!#2!30:(\tikztotarget-|a)$) coordinate (a1)--($ (a1)!#2!60:(a)$) --cycle(a)
      (b)--($ (b)!#2!30:(a)$) coordinate (b1)--($ (b1)!#2!60:(b)$) --cycle(b)
      \pgfextra{ \path[draw,solid,/tikz/line width=\mscget{line width}];}
      (\tikztotarget)
  }},
  measure* style/.default={\mscget{measure distance}}{\mscget{measure symbol width}},
  measure*  style/.style 2 args={%
    /tikz/line width=\mscget{line width}, mscdash,
    to path={
      -- ++(#1,0) coordinate (a)-- (\tikztotarget-|a) coordinate (b)\tikztonodes
      -- (\tikztotarget)
      \pgfextra{ \path[draw,/msc/mscdash,/tikz/line width=\mscget{line width}];}
      (a)--($ (a)!#2!210:(b)$) coordinate (a1)--($ (a1)!#2!60:(a)$) --cycle(a)
      (b)--($ (b)!#2!210:(a)$) coordinate (b1)--($ (b1)!#2!60:(b)$) --cycle(b)
      \pgfextra{ \path[draw,solid,/tikz/line width=\mscget{line width}];}
      (\tikztotarget)
  }},
  measurestart style/.default={\mscget{measure distance}}{\mscget{measure symbol width}},
  measurestart style/.style 2 args={%
    /tikz/line width=\mscget{line width}, mscdash,
    to path={
      -- ++(#1,0) coordinate (a)
      ($ (a)!0.866*#2!(\tikztotarget-|a)$)-- ($(\tikztotarget-|a)! 0.5*#2!(a) $) \tikztonodes
      (\tikztotarget -| a) coordinate (b)
      \pgfextra{ \path[draw,/msc/mscdash,/tikz/line width=\mscget{line width}];}
      (a)--($ (a)!#2!30:(\tikztotarget-|a)$) coordinate (a1)--($ (a1)!#2!60:(a)$) --cycle(a)
      (b) circle (0.5*#2)
      \pgfextra{ \path[draw,solid,/tikz/line width=\mscget{line width}];}
      (\tikztotarget)
  }},
  measurestart* style/.default={\mscget{measure distance}}{\mscget{measure symbol width}},
  measurestart* style/.style 2 args={%
    /tikz/line width=\mscget{line width}, mscdash,
    to path={
      -- ++(#1,0) coordinate (a) -- ($(\tikztotarget-|a)! 0.5*#2!(a) $) \tikztonodes
      (\tikztotarget -| a) coordinate (b)
      \pgfextra{ \path[draw,/msc/mscdash,/tikz/line width=\mscget{line width}];}
      (a)--($ (a)!#2!210:(b)$) coordinate (a1)--($ (a1)!#2!60:(a)$) --cycle(a)
      (b) circle (0.5*#2)
      \pgfextra{ \path[draw,solid,/tikz/line width=\mscget{line width}];}
      (\tikztotarget)
  }},
  found style/.default={2*\mscget{lost symbol radius}},
  found style/.style={%
    /msc, /tikz/line width=\mscget{line width},arrow style,
    to path={
      (\tikztotarget) circle (0.5*#1)
      \pgfextra{ \path[draw,solid,/tikz/line width=\mscget{line width}];}
      ($ (\tikztotarget)! 0.5*#1 !(\tikztostart) $)  -&gt; (\tikztostart)
      \tikztonodes
  }},
  lost style/.default={2*\mscget{lost symbol radius}},
  lost style/.style={%
    /msc, /tikz/line width=\mscget{line width},arrow style,
    to path={
      (\tikztotarget) circle (0.5*#1)
      \pgfextra{ \path[draw,solid,fill,/tikz/line width=\mscget{line width}];}
      (\tikztostart) -&gt; ($ (\tikztotarget)! 0.50*#1 !(\tikztostart) $)
      \tikztonodes
   }},
}
\mscset{normal values}
%special treatments of keys that can be specified as right or left but could not
%be in the old verison of msc
\setlength{\envinstdist}{\mscget{left environment distance}}
\setlength{\inlineoverlap}{\mscget{left inline overlap}}
\setlength{\referenceoverlap}{\mscget{left reference overlap}}
\mscset{
  left environment distance/.initial=\the\envinstdist,      % distance between environments and the % first level
  right environment distance/.initial=\the\envinstdist,      % distance between
  left inline overlap/.initial=\the\inlineoverlap,
  right inline overlap/.initial=\the\inlineoverlap,
  left reference overlap/.initial=\the\referenceoverlap,
  right reference overlap/.initial=\the\referenceoverlap
}
\def\msc@save@target#1{%
  \def\msc@target{#1}}
\def\msc@save@start#1{%
  \def\msc@start{#1}}
%defining styles to draw grid with help lines - usage e.g. \draw (0,-10) to[/msc/color grid] (10,0);
\mscset{
  /msc/grid/.style={
    to path={%
      \pgfextra{%
        \edef\msc@@target{(\tikztotarget)}%
        \tikz@scan@one@point\msc@save@target\msc@@target\relax
        \edef\msc@@start{(\tikztostart)}%
        \tikz@scan@one@point\msc@save@start\msc@@start\relax
        \draw[/msc/grid/minor lines] (\tikztostart) grid (\tikztotarget);
        \draw[/msc/grid/major lines,line cap=rect] (\tikztostart) grid (\tikztotarget);
        \msc@start
        \pgfmathsetmacro{\msc@xa}{\the\pgf@x/1cm}
        \pgfmathsetmacro{\msc@ya}{\the\pgf@y/1cm}
        \msc@target
        \pgfmathsetmacro{\msc@xb}{\the\pgf@x/1cm}
        \pgfmathsetmacro{\msc@yb}{\the\pgf@y/1cm}
        \pgfmathsetmacro{\msc@xc}{\msc@xa + \mscget{grid/major step}}
        \pgfmathsetmacro{\msc@yc}{\msc@ya + \mscget{grid/major step}}
        \foreach \x in {\msc@xa,\msc@xc,...,\msc@xb}
        \node[/msc/grid/x labelstyle] at (\x,\msc@ya) {\pgfmathprintnumber{\x}};
        \foreach \y in {\msc@ya,\msc@yc,...,\msc@yb}
        \node[/msc/grid/y labelstyle] at (\msc@xa,\y) {\pgfmathprintnumber{\y}};
      }
    }
  },
  /msc/color grid/.style={
    /msc/grid/labelstyle/.style={font=\tiny,text=blue},
    /msc/grid/minor line width=0.2pt,
    /msc/grid/major line width=0.4pt,
    /msc/grid/minor lines/.style={
      draw=green!10,line cap=rect,
      /tikz/line width=\mscget{grid/minor line width},
      step=\mscget{grid/minor step}
    },
    /msc/grid/major lines/.style={
      draw=red!10,line cap=rect,
      /tikz/line width=\mscget{grid/major line width},
      step=\mscget{grid/major step}
    },
    /msc/grid
  },
  /msc/grid/.cd,
  minor lines/.style={
    help lines,line cap=rect,dotted,
    step=\mscget{grid/minor step}
  },
  major lines/.style={
    help lines,line cap=rect,
    /tikz/line width=\mscget{grid/major line width},
    step=\mscget{grid/major step}
  },
  labelstyle/.style={font=\scriptsize,text=black},
  x labelstyle/.style={/msc/grid/labelstyle,below},
  y labelstyle/.style={/msc/grid/labelstyle,left},
  minor step/.initial=.2,
  major step/.initial=1,
  minor line width/.initial=0.3pt,
  major line width/.initial=0.5pt,
}
% And some internal counters
\newcount\c@mscinstcnt  %number of intstances
\newcount\c@condition  %number of conditions
\newcount\c@msclevelcnt %current level
% \newcount\c@maxlevelcnt %maximum level seen
%\advance\c@mscinstcnt by1
\global\let\msc@tempa\relax
\global\let\msc@tempb\relax
%\newdimen\msc@x
%\newdimen\msc@y

\newcommand{\mscgetx}[2]{%
  \tikz@scan@one@point\pgfutil@firstofone#1\relax
  \edef#2{\the\pgf@x}%
}

\newcommand{\mscgety}[2]{%
  \tikz@scan@one@point\pgfutil@firstofone#1\relax
  \edef#2{\the\pgf@y}%
}

% store the shifted level in #2 and level at which to draw message in #3
% also update \c@maxlevelcnt
% #1 - level difference
\def\msc@getlevel shift#1#2#3{
    \pgfkeys{/pgf/number format/precision=0}
    \pgfmathparse{\the\c@msclevelcnt + #1}
    \pgfmathparse{max(\pgfmathresult,0)}
    \pgfmathroundto{\pgfmathresult}
    \edef#2{\pgfmathresult} %calculate destination level
    \pgfmathparse{max((\the\c@msclevelcnt),#2)}
    \pgfmathroundto{\pgfmathresult}
    \xdef#3{\pgfmathresult} %calculate at which level to draw message
    \pgfmathparse{max(#3,\c@maxlevelcnt)}
    \pgfmathroundto{\pgfmathresult}
    \xdef\c@maxlevelcnt{\pgfmathresult} %update global max level counter
}

%
% * Shapes *
%
%
%% A rectangle with right side open
%
\pgfdeclareshape{right open rectangle}
{%
  \nodeparts{text}
  %%
  %% Anchors
  %%
  \inheritsavedanchors[from=rectangle]
  \inheritanchorborder[from=rectangle]
  \inheritanchor[from=rectangle]{north}
  \inheritanchor[from=rectangle]{north west}
  \inheritanchor[from=rectangle]{north east}
  \inheritanchor[from=rectangle]{center}
  \inheritanchor[from=rectangle]{west}
  \inheritanchor[from=rectangle]{east}
  \inheritanchor[from=rectangle]{mid}
  \inheritanchor[from=rectangle]{mid west}
  \inheritanchor[from=rectangle]{mid east}
  \inheritanchor[from=rectangle]{base}
  \inheritanchor[from=rectangle]{base west}
  \inheritanchor[from=rectangle]{base east}
  \inheritanchor[from=rectangle]{south}
  \inheritanchor[from=rectangle]{south west}
  \inheritanchor[from=rectangle]{south east}
  \backgroundpath{
   % store lower right in xa/ya and upper right in xb/yb
    \southwest \pgf@xa=\pgf@x \pgf@ya=\pgf@y
    \northeast \pgf@xb=\pgf@x \pgf@yb=\pgf@y
    \pgfpathmoveto{\pgfqpoint{\pgf@xb}{\pgf@yb}}
    \pgfpathlineto{\pgfqpoint{\pgf@xa}{\pgf@yb}}
    \pgfpathlineto{\pgfqpoint{\pgf@xa}{\pgf@ya}}
    \pgfpathlineto{\pgfqpoint{\pgf@xb}{\pgf@ya}}
    \pgfpathmoveto{\pgfqpoint{\pgf@xb}{\pgf@yb}}
    \pgfpathclose
   }
}
%
%% A rectangle with left side open
%
\pgfdeclareshape{left open rectangle}
{%
  \nodeparts{text}
  %%
  %% Anchors
  %%
  \inheritsavedanchors[from=rectangle]
  \inheritanchorborder[from=rectangle]
  \inheritanchor[from=rectangle]{north}
  \inheritanchor[from=rectangle]{north west}
  \inheritanchor[from=rectangle]{north east}
  \inheritanchor[from=rectangle]{center}
  \inheritanchor[from=rectangle]{west}
  \inheritanchor[from=rectangle]{east}
  \inheritanchor[from=rectangle]{mid}
  \inheritanchor[from=rectangle]{mid west}
  \inheritanchor[from=rectangle]{mid east}
  \inheritanchor[from=rectangle]{base}
  \inheritanchor[from=rectangle]{base west}
  \inheritanchor[from=rectangle]{base east}
  \inheritanchor[from=rectangle]{south}
  \inheritanchor[from=rectangle]{south west}
  \inheritanchor[from=rectangle]{south east}
  \backgroundpath{
   % store lower right in xa/ya and upper right in xb/yb
    \southwest \pgf@xa=\pgf@x \pgf@ya=\pgf@y
    \northeast \pgf@xb=\pgf@x \pgf@yb=\pgf@y
    \pgfpathmoveto{\pgfqpoint{\pgf@xa}{\pgf@ya}}
    \pgfpathlineto{\pgfqpoint{\pgf@xb}{\pgf@ya}}
    \pgfpathlineto{\pgfqpoint{\pgf@xb}{\pgf@yb}}
    \pgfpathlineto{\pgfqpoint{\pgf@xa}{\pgf@yb}}
    \pgfpathmoveto{\pgfqpoint{\pgf@xa}{\pgf@ya}}
    \pgfpathclose
   }
}
%
%% A rectangle with sloped sides
%
\pgfdeclareshape{condition shape}
{%
  \nodeparts{text}
  %%
  %% Anchors
  %%
  \inheritsavedanchors[from=rectangle]
  \inheritanchorborder[from=rectangle]
  \inheritanchor[from=rectangle]{north}
  \inheritanchor[from=rectangle]{north west}
  \inheritanchor[from=rectangle]{north east}
  \inheritanchor[from=rectangle]{center}
  \inheritanchor[from=rectangle]{west}
  \inheritanchor[from=rectangle]{east}
  \inheritanchor[from=rectangle]{mid}
  \inheritanchor[from=rectangle]{mid west}
  \inheritanchor[from=rectangle]{mid east}
  \inheritanchor[from=rectangle]{base}
  \inheritanchor[from=rectangle]{base west}
  \inheritanchor[from=rectangle]{base east}
  \inheritanchor[from=rectangle]{south}
  \inheritanchor[from=rectangle]{south west}
  \inheritanchor[from=rectangle]{south east}
  \backgroundpath{
   % store lower right in xa/ya and upper right in xb/yb
    % store lower right in xa/ya and upper right in xb/yb
    \southwest \pgf@xa=\pgf@x \pgf@ya=\pgf@y
    \northeast \pgf@xb=\pgf@x \pgf@yb=\pgf@y
    \pgfpathmoveto{\pgfqpoint{\pgf@xb}{\pgf@yb}}
    \pgfpathlineto{\pgfqpoint{\pgf@xa}{\pgf@yb}}
    \pgfmathparse{\pgf@xa-(\pgf@yb-\pgf@ya)*0.5}
    \pgf@xc=\pgfmathresult pt\relax
    \pgfmathparse{\pgf@yb*0.5+\pgf@ya*0.5}
    \pgf@yc=\pgfmathresult pt\relax
    \pgfpathlineto{\pgfqpoint{\pgf@xc}{\pgf@yc}}
    \pgfpathlineto{\pgfqpoint{\pgf@xa}{\pgf@ya}}
    \pgfpathlineto{\pgfqpoint{\pgf@xb}{\pgf@ya}}
    \pgfmathparse{\pgf@xb+(\pgf@yb-\pgf@ya)*0.5}
    \pgf@xc=\pgfmathresult pt\relax
    \pgfmathparse{\pgf@yb*0.5+\pgf@ya*0.5}
    \pgf@yc=\pgfmathresult pt\relax
    \pgfpathlineto{\pgfqpoint{\pgf@xc}{\pgf@yc}}
    \pgfpathlineto{\pgfqpoint{\pgf@xb}{\pgf@yb}}
    \pgfpathclose
   }
}
%% A rectangle with sloped sides and strike out
%
\pgfdeclareshape{ncondition shape}
{%
  \nodeparts{text}
  %%
  %% Anchors
  %%
  \inheritsavedanchors[from=rectangle]
  \inheritanchorborder[from=rectangle]
  \inheritanchor[from=rectangle]{north}
  \inheritanchor[from=rectangle]{north west}
  \inheritanchor[from=rectangle]{north east}
  \inheritanchor[from=rectangle]{center}
  \inheritanchor[from=rectangle]{west}
  \inheritanchor[from=rectangle]{east}
  \inheritanchor[from=rectangle]{mid}
  \inheritanchor[from=rectangle]{mid west}
  \inheritanchor[from=rectangle]{mid east}
  \inheritanchor[from=rectangle]{base}
  \inheritanchor[from=rectangle]{base west}
  \inheritanchor[from=rectangle]{base east}
  \inheritanchor[from=rectangle]{south}
  \inheritanchor[from=rectangle]{south west}
  \inheritanchor[from=rectangle]{south east}
  \backgroundpath{
   % store lower right in xa/ya and upper right in xb/yb
    % store lower right in xa/ya and upper right in xb/yb
    \southwest \pgf@xa=\pgf@x \pgf@ya=\pgf@y
    \northeast \pgf@xb=\pgf@x \pgf@yb=\pgf@y
    \pgfpathmoveto{\pgfqpoint{\pgf@xb}{\pgf@yb}}
    \pgfpathlineto{\pgfqpoint{\pgf@xa}{\pgf@yb}}
    \pgfpathlineto{\pgfqpoint{\pgf@xb}{\pgf@ya}}
    \pgfpathmoveto{\pgfqpoint{\pgf@xa}{\pgf@ya}}
    \pgfpathlineto{\pgfqpoint{\pgf@xb}{\pgf@yb}}
    \pgfpathmoveto{\pgfqpoint{\pgf@xa}{\pgf@yb}}
    \pgfmathparse{\pgf@xa-(\pgf@yb-\pgf@ya)*0.5}
    \pgf@xc=\pgfmathresult pt\relax
    \pgfmathparse{\pgf@yb*0.5+\pgf@ya*0.5}
    \pgf@yc=\pgfmathresult pt\relax
    \pgfpathlineto{\pgfqpoint{\pgf@xc}{\pgf@yc}}
    \pgfpathlineto{\pgfqpoint{\pgf@xa}{\pgf@ya}}
    \pgfpathlineto{\pgfqpoint{\pgf@xb}{\pgf@ya}}
    \pgfmathparse{\pgf@xb+(\pgf@yb-\pgf@ya)*0.5}
    \pgf@xc=\pgfmathresult pt\relax
    \pgfmathparse{\pgf@yb*0.5+\pgf@ya*0.5}
    \pgf@yc=\pgfmathresult pt\relax
    \pgfpathlineto{\pgfqpoint{\pgf@xc}{\pgf@yc}}
    \pgfpathlineto{\pgfqpoint{\pgf@xb}{\pgf@yb}}
    \pgfpathclose
   }
}


% \declinst[*] declares a new msc-instance and draws its head symbol
% the starred versions makes a fat instance.
% #1: msc/tikz options
% #2: nickname that can be used in \mess
% #3: name of the instance (above instance head symbol)
% #4: name of the instance (inside instance head symbol)
% Keys used:
% /msc/instance/nick - contains number for instance with nick
% /msc/instanceno/n - contains nick for instance with n, where n is a number
%\declinst(*){nickname}{instancenameabove}{instancenamewithin}
\def\declinst{\pgfutil@ifnextchar*{\msc@isstartrue\msc@declinst@nostar}{\msc@isstarfalse\msc@declinst@nostar*}}
\def\msc@declinst@nostar*{\pgfutil@ifnextchar[\msc@declinst@noopt{\msc@declinst@noopt[]}}
\def\msc@declinst@noopt[#1]#2#3#4{%
  \msc@nameinstance{#2}{#1}
  \msc@previousinstance{#2}
  \begin{pgfscope}
  \mscset{#1}
    \node[/msc,draw=\mscget{draw head},
          instance head={#3}, name={msc@node#2},
          right=\mscget{instance distance} of msc@node\msc@inst@name.south east,
%           inner sep=2pt,
          anchor=south west, every instance head,#1]{#4};
  \end{pgfscope}
  \advance\c@msclevelcnt by -1\relax
  \msc@createlevelnodes{#2}{0}
  \coordinate (msc@lastlevel#2) at (msc@node#2.south);
  \advance\c@msclevelcnt by 1\relax
  \msc@drawinstanceline{#2}{1}
}
% \dummyinst(*)[options]{createdinst}
\def\dummyinst{\pgfutil@ifnextchar*{\msc@isstartrue\msc@dummyinst@nostar}{\msc@isstarfalse\msc@dummyinst@nostar*}}
\def\msc@dummyinst@nostar*{\pgfutil@ifnextchar[\msc@dummyinst@noopt{\msc@dummyinst@noopt[]}}
\def\msc@dummyinst@noopt[#1]#2{%
  \msc@nameinstance{#2}{#1}
  \mscset{
    instance/#2/status/.initial=off
   }
  \begin{pgfscope}
    \mscset{#1}
    \msc@previousinstance{#2}
    \pgfmathparse{max(\mscget{instance width}, width(\mscget{dummy text})
                  +\pgfkeysvalueof{/pgf/inner xsep}*2+\mscget{line width}/2)}
    \edef\msc@x{\pgfmathresult pt}
    \node[/msc, name={msc@node#2},
          inner sep=2pt,
          right=\mscget{instance distance} of msc@node\msc@inst@name.south east,
          minimum width=\msc@x,
          minimum height=\mscget{head height},
          anchor=south west, #1]{};
  \end{pgfscope}
  \advance\c@msclevelcnt by -1\relax
  \msc@createlevelnodes{#2}{0}
  \coordinate (msc@lastlevel#2) at (msc@node#2.south);
  \advance\c@msclevelcnt by 1\relax
}

\def\inststart{\startinst}%old name of the command
%dd siple command \startinst[options]{instname}{text above}{text inside}
\def\startinst{\pgfutil@ifnextchar[\msc@startinst{\msc@startinst[]}}
\def\msc@startinst[#1]{
  \begin{pgfscope}
  \edef\msc@option{#1}\edef\msc@name{}\edef\msc@creator{}
  \pgfkeysactivatefamily{/msc/message options}
  \pgfkeysfiltered{/msc,#1}
  \msc@create
}
% \create[options]{name}[label position]{creator}[pos]{createdinst}{instancenameabove}{instancenamewithin}
\def\create{
  \begin{pgfscope}
  \def\msc@option{}
  \pgfutil@ifnextchar[\msc@create@opt{\msc@create@opt[]}
}
\def\msc@create@opt[#1]#2{
    \pgfkeysactivatefamily{/msc/message options}
    \pgfkeysfiltered{/msc,#1}
    \edef\msc@option{#1}
    \def\msc@name{#2}
    \pgfutil@ifnextchar[\msc@create@label{\msc@create@label[]}
}
\def\msc@create@label[#1]#2{
    \ifx#1t \mscset{label position=above}
    \else \ifx#1b \mscset{label position=below}
    \fi\fi
    \edef\msc@creator{#2}
    \pgfutil@ifnextchar[\msc@create{\msc@create@pos[\mscget{pos}]}
}
\def\msc@create@pos[#1]{
    \mscset{pos/.expanded=#1}
    \msc@create
}
%\create{insance name}{label above}{label inside}
\def\msc@create#1#2#3{
%     \mscset{pos/.expanded=#1}
    \pgfkeysifdefined{/msc/instance/#1/no}{
      \IfStrEq{off}{\mscget{instance/#1/status}}{
        \IfStrEq{fat}{\mscget{instance/#1/type}}{
          \edef\msc@tempa{(msc@node#1.east)++(-\mscget{line width}/2,0) coordinate (msc@node#1@r0)
               coordinate (msc@node#1@r\the\c@msclevelcnt)
              (msc@node#1.west)++(\mscget{line width}/2,0) coordinate (msc@node#1@l0)
               coordinate (msc@node#1@l\the\c@msclevelcnt)}
        }{%
          \edef\msc@tempa{(msc@node#1.east)++(-\mscget{line width}/2,0)
               coordinate (msc@node#1@r\the\c@msclevelcnt)
              (msc@node#1.west)++(\mscget{line width}/2,0)
               coordinate (msc@node#1@l\the\c@msclevelcnt)}
        }
        \edef\msc@tempb{
          [/msc, draw=\mscget{draw head}, instance head={#2}, name={msc@node#1}, every
          instance head,
          append after command={(msc@node#1.south) coordinate (msc@lastlevel#1)
              \msc@tempa},
          \msc@option] at (msc@node#1|-msc@level\the\c@msclevelcnt){\unexpanded\expandafter{#3}};
        }
        \adddraw{#1}{\the\c@msclevelcnt}{\expandafter\node\msc@tempb}
        \pgfkeysifdefined{/msc/instance/\msc@creator/no}{
          \edef\msc@tempb{[\msc@option]{\unexpanded\expandafter{\msc@name}}{\msc@creator}{#1}}
          \expandafter\mess\msc@tempb
        }{}
        \end{pgfscope}
        \mscset{instance/#1/status=on}
      }{
        \msc@instancestarted{#1}\end{pgfscope}
      }
%      \mscset{instance/#1/type=fat}
    }{\msc@instundefinederr{#1}\end{pgfscope}}
}

% creates nodes to which we draw a line when advancing a level
% #1 instance name
%associates name with number #1 in corresponding pgfkeys. It updates
%the right evironment
  % #1 name of instance
  % #2 options
\def\msc@nameinstance#1#2{
 \pgfkeysifdefined{/msc/instance/#1/no}{
   \msc@nicknamedefinederr{#1}
  }{
    \advance\c@mscinstcnt by2\relax
    \mscset{%update envright keys
      instance/envright/no/.initial/.expanded=\the\c@mscinstcnt,
      instanceno/\the\c@mscinstcnt/name/.initial/.expanded=envright
    }
    \advance\c@mscinstcnt by-1\relax%
    \mscset{
       instance/#1/no/.initial/.expanded=\the\c@mscinstcnt,
       instanceno/\the\c@mscinstcnt/name/.initial/.expanded=#1,%
       instance/#1/status/.initial=on,      %possible values: on, off (no draw),
       instance/#1/cover/.initial=0,        %how many times instance is covered
       instance/#1/region/.initial=normal,  %possible %values:normal,coregion,suspension,activation,seminormal
       instance/#1/region level/.initial=0,
       instance/#1/region width/.initial=0pt
    }
  }
  \begin{pgfscope}%parse options in scope not to propagate them
    \mscset{#2}%
    \ifnum\c@mscinstcnt&lt;2\relax  %the first instance
      \coordinate[below=\mscget{first level height} of msc@level0] (msc@level1);
    \fi
    \ifmsc@isstar
      \xdef\msc@tempa{fat}
    \else
      \xdef\msc@tempa{\mscget{fat}}
    \fi
  \end{pgfscope}
  \mscset{/msc/instance/#1/type/.initial/.expand once=\msc@tempa}
  \iftikz@fullytransformed  %when fully transformed lines width is wrong - submitted bug nr 3597513.
    \pgfmathparse{\msc@tempa + (0.5-0.5/\pgf@pt@bb)*\mscget{line width}}
    \xdef\msc@tempa{\pgfmathresult}
  \fi
}
%assigns the name of the previous instance to the \msc@inst@name
  % #1 name or number of the instance
\def\msc@previousinstance#1{%
   \pgfkeysifdefined{/msc/instanceno/#1/name}%
     { \pgfmathsetcount{\c@pgf@counta}{#1} }
     { \pgfkeysifdefined{/msc/instance/#1/no}
       {\pgfmathsetcount{\c@pgf@counta}{\mscget{instance/#1/no}}}%
       {\msc@instundefinederr{#1}}
     }
  \advance\c@pgf@counta by -1\relax%
  \edef\msc@inst@name{\mscget{instanceno/\the\c@pgf@counta/name}}
}

\def\msc@numsplit#1.#2{\def\msc@ta{#1}\def\msc@tb{#2}}
% \nextlevel increases \msc@currentheight by #1 * \level height
% (optional) #1: a nonnegative integer number (defaults to 1)
% or tkiz options
%
\def\nextlevel{
  \pgfutil@ifnextchar[\msc@nextlevelopt{\msc@nextlevelopt[1]}
}
\def\msc@nextlevelopt[#1]{%
  \let\msc@tempheight\relax
  \if!\ifnum9&lt;1#1!\else_\fi
    \mscset{/msc/level offset=#1}
  \else
    \msc@numsplit#1\relax
    \if!\ifnum9&lt;1\msc@ta!\else_\fi
      \mscset{/msc/level offset=\msc@ta}%we get only 
      \if!\ifnum9&lt;1\msc@tb!\else_\fi
       \pgfmathsetmacro{\msc@tempheight}{0.\msc@tb*\mscget{level height}}
       \msc@notpositiveintegerwarn{\msc@ta}{\msc@tb}
      \fi
    \fi
  \fi
  \mscgety{(msc@level\the\c@msclevelcnt)}{\msc@y}
  \foreach \msc@tempa [evaluate=\msc@tempc using \msc@y-(\msc@tempa*\mscget{level height})] in {1 ,...,\mscget{level offset}} {%
    \advance\c@msclevelcnt by 1\relax
    \coordinate (msc@level\the\c@msclevelcnt) at (0,\msc@tempc pt);
    \advance\c@msclevelcnt by -1\relax
    \foreach \msc@tempb in {1,...,\c@mscinstcnt} {
      \msc@createlevelnodes{\mscget{instanceno/\msc@tempb/name}}{\the\c@msclevelcnt}
    }
%        \message{-----Showing code for level=\the\c@msclevelcnt------------------- }
%          \pgfkeys{/msc/level\the\c@msclevelcnt/draw/.show code,}
    \pgfkeysifdefined{/msc/level\the\c@msclevelcnt/havedraw}{
      \begin{pgfscope}
         \mscset{/msc/level\the\c@msclevelcnt/draw}
         \msc@global@set{/msc/level\the\c@msclevelcnt/draw/.code={}}
      \end{pgfscope}
    }{
    }
    \global\advance\c@msclevelcnt by 1\relax
  }
  \foreach \msc@tempb in {1,...,\c@mscinstcnt} {
    \msc@drawinstanceline{\mscget{instanceno/\msc@tempb/name}}{\the\c@msclevelcnt}
  }
 \ifx\msc@tempheight\relax\else
   \edef\msc@ta{\mscget{level height}}
   \mscset{level height/.expanded=\msc@tempheight pt}
   \nextlevel[1]
   \mscset{level height/.expanded=\msc@ta}
 \fi
 \mscset{level offset=1}
}

% \coordinate (msc@level\the\c@msclevelcnt) at (0,#2);
% draw a line for a given instance
%  #1 name of the instance
%  #2 level number
\def\msc@drawinstanceline#1#2{
  \IfStrEq{\mscget{instance/#1/status}}{on}{
%     ifnum0&lt;\mscget{instance/#1/cover} \else
      \mscgety{(msc@level#2)}{\msc@tempa}
      \mscgety{(msc@lastlevel#1)}{\msc@dil}
      \pgfmathparse{max(\msc@tempa-\msc@dil,\mscget{instance/#1/cover})}
      \ifnum0&lt;\pgfmathresult\relax %draw only if last level is above current level
        \mscgety{(msc@level#2)}{\msc@io}\msc@setlastlevel{#1}{\msc@io}
      \else
        \msc@StrEqEither{\mscget{instance/#1/region}}{normal}{seminormal}{
            \draw[/msc,instance line,every instance line]
              (msc@lastlevel#1-|msc@node#1@l0)--(msc@level#2-|msc@node#1@l0)
              (msc@lastlevel#1-|msc@node#1@r0)--(msc@level#2-|msc@node#1@r0);
            \mscgety{(msc@level#2)}{\msc@io}\msc@setlastlevel{#1}{\msc@io}
         }{
%            \msc@regbody{#1}{#2}
         }
      \fi
  }{}
}

% create nodes at a current level for a given instance
%  #1 name of the instance
%  #2 level number
\def\msc@createlevelnodes#1#2{
%assume node msc@level#2 exists
    \IfEqCase{\mscget{instance/#1/type}}{
      {fat} {
       \coordinate[xshift=\mscget{line width} /2](msc@node#1@l#2) at (msc@node#1.west|-msc@level#2);
       \coordinate[xshift=-\mscget{line width} /2] (msc@node#1@r#2) at (msc@node#1.east|-msc@level#2);
       \IfStrEq{\mscget{instance/#1/region}}{seminormal}{
          \msc@global@set{instance/#1/region=normal}
        }{}
      }
      {normal} {%
        \msc@StrEqEither{\mscget{instance/#1/region}}{normal}{coregion}{%
            \coordinate (msc@node#1@r#2) at (msc@node#1 |-msc@level#2);
            \coordinate (msc@node#1@l#2) at (msc@node#1 |-msc@level#2);
        }
        {%
          \msc@StrEqEither{\mscget{instance/#1/region}}{activation}{suspension} {
            \path let \p1=(msc@node#1), \p2=(msc@level#2) in
              coordinate(msc@node#1@l#2) at (\x1-\mscget{instance/#1/region width}/2,\y2)
              coordinate(msc@node#1@r#2) at (\x1+\mscget{instance/#1/region width}/2,\y2);
          }
          {
            \IfStrEq{\mscget{instance/#1/region}}{seminormal}{
              \path let \p1=(msc@node#1), \p2=(msc@level#2) in
              coordinate(msc@node#1@l#2) at (\x1-\mscget{instance/#1/region width}/2,\y2)
              coordinate(msc@node#1@r#2) at (\x1+\mscget{instance/#1/region width}/2,\y2);
              \msc@global@set{instance/#1/region=normal}
            }{%debug message
              \message{[msc] Unknown region type: \mscget{instance/#1/region} for the nick: #1}
            }
          }
        }
      }
      [\message{[msc] Unknown instance type: \mscget{instance/#1/type} for the nick: #1}]
    }
%   }
%   { }
}
% \mess(*)[side]{name}[label position]{sender}[pos]{receiver}[level shift]
\def\mess{
  \begin{pgfscope}
    \def\msc@options{}
    \pgfutil@ifnextchar*{\msc@isstartrue\msc@mess@nostar}{\msc@isstarfalse\msc@mess@nostar*}
}
\def\msc@mess@nostar*{\pgfutil@ifnextchar[\msc@messopt{\msc@messopt[]}}
\def\msc@messopt[#1]{%parsing of [side] and [options]
  \ifx#1l \mscset{side=left}
  \else \ifx#1r \mscset{side=right}
  \else \ifx#1b \else \ifx#1t %ignoring t and b for backward compatibility
    \else
      \pgfkeysactivatefamily{/msc/message options}
      \pgfkeysfiltered{/msc,#1}
      \def\msc@options{#1}
%       \pgfutil@ifundefined{msc@mess@side}{\def\msc@mess@side{\mscget{side}}}{}
     \fi \fi \fi
  \fi
  \pgfutil@ifnextchar[{\msc@messopt}{\msc@mess@threeopt}
}
\def\msc@mess@threeopt#1{%parsing of {name}
  \def\msc@mess@name{#1}
  \pgfutil@ifnextchar[\msc@mess@twoopt{\msc@mess@twoopt[\mscget{label position}]}
}
\def\msc@mess@twoopt[#1]#2{%parsing of [label position] and {sender}
  \ifx#1l \mscset{label position=left}
  \else \ifx#1r \mscset{label position=right}
  \else \ifx#1t \mscset{label position=above}
  \else \ifx#1b \mscset{label position=below}
  \fi \fi \fi \fi
  \xdef\msc@sender{#2}
  \pgfutil@ifnextchar[\msc@mess@oneopt{\msc@mess@oneopt[\mscget{pos}]}
}
\def\msc@mess@oneopt[#1]#2{%parsing of [placement] and {receiver}
  \mscset{pos/.expanded=#1}
  \xdef\msc@receiver{#2}
  \IfStrEq{\msc@receiver}{\msc@sender}{
    \edef\msc@tempb{\mscget{offset}}
  }{
    \edef\msc@tempb{\mscget{level shift}}
  }
  \pgfutil@ifnextchar[{\msc@mess@noopt}{\msc@mess@noopt[\msc@tempb]}
}

\def\msc@mess@noopt[#1]{%parsing of [level shift]
  \def\msc@undefined{false}
  \msc@getlevel shift{#1}{\msc@level shift}{\msc@tempa}
  \ifx\msc@sender\msc@receiver  %self message
    \IfStrEq{\mscget{label position}}{above}{
      \mscset{label position=\mscget{side}}
    }{}
    \pgfkeysifdefined{/msc/instance/\msc@receiver/no}{%instance name
      \IfStrEq{\mscget{side}}{left}{
        \msc@selfmess{msc@node\msc@receiver @l\the\c@msclevelcnt}{msc@node\msc@receiver @l\msc@level shift}{-\mscget{self message width}}
      }{
        \msc@selfmess{msc@node\msc@receiver @r\the\c@msclevelcnt}{msc@node\msc@receiver @r\msc@level shift}{\mscget{self message width}}
      }
    }{
      \pgfutil@ifundefined{pgf@sh@ns@msc@node\msc@receiver}{% neither instance name nor reference node
        \def\msc@undefined{true}
        \msc@instundefinederr{\msc@receiver}
      }{%  reference node
        \IfStrEq{\mscget{side}}{left}{
          \msc@selfmess{msc@node\msc@receiver|-msc@level\the\c@msclevelcnt}%
          {msc@node\msc@receiver|-msc@level\msc@level shift}{-\mscget{self message width}}
        }{
          \msc@selfmess{msc@node\msc@receiver|-msc@level\the\c@msclevelcnt}%
          {msc@node\msc@receiver|-msc@level\msc@level shift} {\mscget{self message width}}
        }
      }
    }
  \else %not self message
    \pgfutil@ifundefined{pgf@sh@ns@msc@node\msc@receiver} {
      \def\msc@undefined{true}
      \msc@instundefinederr{\msc@receiver}
    }{
      \mscgetx{(msc@node\msc@receiver)}{\msc@minx}
    }
    \pgfutil@ifundefined{pgf@sh@ns@msc@node\msc@sender} {
      \def\msc@undefined{true}
      \msc@instundefinederr{\msc@sender}
    }{
      \mscgetx{(msc@node\msc@sender)}{\msc@maxx}
    }
    \IfStrEq{\msc@undefined}{false}{
      \pgfkeysifdefined{/msc/instance/\msc@sender/no}{%instance name
%        \pgfmathparse{\msc@maxx-\msc@minx}
        \pgfmathparse{ifthenelse((\msc@maxx-\msc@minx)&lt;0,"r","l")}
        \edef\msc@left{msc@node\msc@sender @\pgfmathresult\the\c@msclevelcnt}
      }{
        \def\msc@left{msc@node\msc@sender|-msc@level\the\c@msclevelcnt}
      }
      \pgfkeysifdefined{/msc/instance/\msc@receiver/no}{%instance name
        \pgfmathparse{ifthenelse((\msc@maxx-\msc@minx)&lt;0,"l","r")}
        \edef\msc@right{msc@node\msc@receiver @\pgfmathresult\msc@level shift}
      }{
       \def\msc@right{msc@node\msc@receiver|-msc@level\msc@level shift}
      }
      \msc@mess{\msc@left}{\msc@right}%stores result in \msc@tempb
    }{}
  \fi
  \IfStrEq{\msc@undefined}{false}{
    \end{pgfscope}
    \addDdraw{\msc@sender}{\msc@receiver}{\msc@tempa}{\expandafter\draw\msc@tempb}
  }{
    \end{pgfscope}
  }
}
% #1 - sender node
% #2 - receiver node
% #3 - message dist
% result defined in \msc@tempb
\def\msc@selfmess#1#2#3{
  \IfStrEq{\mscget{label position}}{left}{\xdef\msc@tempc{-1}}{\xdef\msc@tempc{1}}
  \xdef\msc@tempb{[\mscget{label position},/msc,message,message loop={#3},
            \ifmsc@isstar replay,\fi, inner sep=0pt, 
           /tikz/pos=\mscget{pos}, every message, \msc@options]
           (#1)
              to node[xshift=\msc@tempc*\mscget{label distance}](msc@lastnode){\expandafter\noexpand\msc@mess@name}
           (#2);
          }%use macro to expand parameters
}
% #1 - sender node
% #2 - receiver node
% result defined in \msc@tempb
\def\msc@mess#1#2{
  \IfSubStr{\mscget{label position}}{above}{\xdef\msc@tempc{1}}{\xdef\msc@tempc{-1}}
  \xdef\msc@tempb{[/msc,\mscget{label position},message,
          \ifmsc@isstar replay,\fi, inner sep=0pt, %
         /tikz/pos=\mscget{pos}, every message, \msc@options]
         (#1) -&gt;
         node[yshift=\msc@tempc*\mscget{label distance}](msc@lastnode){\unexpanded\expandafter{\msc@mess@name}}(#2);%cheating %and using eTeX expansion
         % to use pure TeX see http://tex.stackexchange.com/questions/40674/replacement-for-unexpanded-without-etex-extension
  }
}
%add code to be executed at given level
% #1 - name of the instance
% #2 - number of level at which to add the code
% #3 - code to be added (expanded once - so prefix with \expandafter)
\def\adddraw#1#2#3{
  \msc@StrEqEither{#1}{envright}{envleft} {
    \msc@global@set{/msc/levelenv/draw/.append code/.expand once={#3},
           /msc/levelenv/havedraw/.initial=true}
  }{
    \msc@global@set{/msc/level#2/draw/.append code/.expand once={#3},
          /msc/level#2/havedraw/.initial=true}
  }
}
%add code to be executed at given level
% #1 - name of the instance
% #2 - name of the second instance
% #3 - number of level at which to add the code
% #4 - code to be added (expanded once - so prefix with \expandafter)
\def\addDdraw#1#2#3#4{
  \msc@StrEqEither{#1}{envright}{envleft} {
    \msc@global@set{/msc/levelenv/draw/.append code/.expand once={#4},
            /msc/levelenv/havedraw/.initial=true}
  }{
    \msc@StrEqEither{#2}{envright}{envleft} {
      \msc@global@set{/msc/levelenv/draw/.append code/.expand once={#4},
            /msc/levelenv/havedraw/.initial=true}
    }{
      \msc@global@set{/msc/level#3/draw/.append code/.expand once={#4},
          /msc/level#3/havedraw/.initial=true}
    }
  }
}
% \msccomment[position]{text}{instname}
\def\msccomment{
 \begin{pgfscope}
  \def\msc@options{}
  \pgfutil@ifnextchar*{\msc@isstartrue\msc@msccomment@nostar}{\msc@isstarfalse\msc@msccomment@nostar*}
}
\def\msc@msccomment@nostar*{\pgfutil@ifnextchar[\msc@msccomment@opt{\msc@msccomment@opt[]}}
\def\msc@msccomment@opt[#1]{%parsing of [side] and [options]
  \ifx#1l \mscset{side=left}
  \else \ifx#1r \mscset{side=right}
    \else
      \pgfkeysactivatefamily{/msc/msccomment options}
      \pgfkeysfiltered{/msc,#1}
      \def\msc@options{#1}
%       \pgfutil@ifundefined{msc@mess@side}{\def\msc@mess@side{\mscget{side}}}{}
     \fi
  \fi
  \pgfutil@ifnextchar[{\msc@msccomment@opt}{\msc@msccomment@noopt}
}

\def\msc@msccomment@noopt#1#2{%parsing of {text}
  \edef\msc@undefined{false}
  \edef\msc@instname{#2}
  \pgfkeysifdefined{/msc/instance/\msc@instname/no}{
    \IfStrEq{\mscget{side}}{left}{
      \edef\msc@node{msc@node\msc@instname @l\the\c@msclevelcnt}
     } {
      \edef\msc@node{msc@node\msc@instname @r\the\c@msclevelcnt}
    }
  }{
    \pgfutil@ifundefined{pgf@sh@ns@msc@node\msc@instname}{% neither instance name nor reference node
      \edef\msc@undefined{true}
      \msc@instundefinederr{\msc@instname}
    }
    {
      \edef\msc@node{msc@node\msc@instname|-msc@level\the\c@msclevelcnt}
    }
  }
  \IfStrEq{\msc@undefined}{false}{
    \IfStrEq{\mscget{side}}{left}{
      \def\msc@anchor{east}
      \edef\msc@dist{-\mscget{msccomment distance}}
     } {
      \def\msc@anchor{west}
      \edef\msc@dist{\mscget{msccomment distance}}
    }
    \xdef\msc@tempb{[/msc,msccomment,msccomment line,
            every msccomment, \msc@options]
            let \noexpand\p1 = (\msc@node)
            in (\noexpand\x1+\msc@dist,\noexpand\y1)
            node [/msc,draw,solid,\mscget{side} open rectangle,anchor=\msc@anchor,
            append after command={(\msc@node)
              -- (\noexpand\tikzlastnode)},
            every msccomment, \msc@options] {#1};
          }%use macro to expand parameters
    \end{pgfscope}
    \adddraw{#2}{\the\c@msclevelcnt}{\expandafter\draw\msc@tempb}
  }{
    \msc@instundefinederr{\msc@instname}\end{pgfscope}
  }
}
% \action(*){name}{instance}
% \naction(*){name}{instance}
\def\naction{
 \begin{pgfscope}%,append after command={node[draw,cross out]{}}
  \def\msc@crossout{,append after command={
      [shorten &gt;=1.2*\noexpand\mscget{line width},
       shorten &lt;=1.2*\noexpand\mscget{line width}]
      (\noexpand\tikzlastnode.north west) edge (\noexpand\tikzlastnode.south east)
      (\noexpand\tikzlastnode.north east) edge (\noexpand\tikzlastnode.south west)}}
  \pgfutil@ifnextchar*{\msc@isstartrue\msc@action@nostar}{\msc@isstarfalse\msc@action@nostar*}
}
\def\action{
 \begin{pgfscope}
  \def\msc@crossout{}
  \def\msc@options{}
  \pgfutil@ifnextchar*{\msc@isstartrue\msc@action@nostar}{\msc@isstarfalse\msc@action@nostar*}
}
% #1 options
% #2 name
% #3 insstance
\def\msc@action@nostar*{\pgfutil@ifnextchar[\msc@action@opt{\msc@action@opt[]}}
\def\msc@action@opt[#1]#2#3{%parsing of [side] and [options]
  \pgfkeysactivatefamily{/msc/action options}
  \pgfkeysfiltered{/msc,#1}
  \def\msc@options{#1}
  \xdef\msc@instname{#3}
  \ifmsc@isstar
    \def\msc@tempa{}
  \else
    %\msc@savebox{#2}
    \edef\msc@tempa{,
       %text height={min({\the\ht\msc@box},\mscget{action height})},
       %text depth={\the\dp\msc@box},
                 %inner sep=0,
                 align=center,
                 text width={max( \mscget{action width},\noexpand\noexpand\noexpand\x2 -
                 \noexpand\noexpand\noexpand\x1)-2*\mscget{label distance}}
                 }
  \fi
  \pgfkeysifdefined{/msc/instance/\msc@instname/no}{
    \xdef\msc@tempb{[, ]
            let \noexpand\p1 = (msc@node\msc@instname @l\the\c@msclevelcnt),
            \noexpand\p2 = (msc@node\msc@instname @r\the\c@msclevelcnt) in
            ( {\noexpand\x1+(\noexpand\x2-\noexpand\x1)/2},\noexpand\y1)
             node[/msc, line cap=round,
               yshift=\mscget{line width}/2, anchor=north,
               minimum height=\mscget{action height},
               minimum width= {max( \mscget{action width},\noexpand\x2 -
               \noexpand\x1)} \msc@tempa, draw \msc@crossout,
               inner sep=\mscget{label distance},
               every action, /tikz/line width=\mscget{line width},\msc@options 
            ](msc@tempnode){\unexpanded\expandafter{#2}};
            \noexpand\msc@StrEqEither{\msc@instname}{envright}{envleft}{}{
              \noexpand\mscgety{(msc@tempnode.south)}{\noexpand\msc@y}
              \noexpand\msc@setlastlevel{\msc@instname}{\noexpand\msc@y}
            }
          }
    \end{pgfscope}
    \msc@StrEqEither{\mscget{instance/#3/region}}{normal}{seminormal}{}{
      \msc@regbody{#3}{\the\c@msclevelcnt}
      \msc@regbar{#3}{\mscget{instance/#3/region level}}
    }
    \adddraw{\msc@instname}{\the\c@msclevelcnt}{\expandafter\draw\msc@tempb}
  }{
    \msc@instundefinederr{\msc@instname}\end{pgfscope}
  }
}
% \settimer[placement]{name}{instance}
\def\settimer{
 \begin{pgfscope}
  \def\msc@options{} \def\msc@timertype{settimer style}
  \pgfutil@ifnextchar[\msc@timer@opt{\msc@timer@opt[]}
}
% \timeout[placement]{name}{instance}
\def\timeout{
 \begin{pgfscope}
  \def\msc@options{} \def\msc@timertype{timeout style}
  \pgfutil@ifnextchar[\msc@timer@opt{\msc@timer@opt[]}
}
% \stoptimer[placement]{name}{instance}
\def\stoptimer{
 \begin{pgfscope}
  \def\msc@options{} \def\msc@timertype{stoptimer style}
  \pgfutil@ifnextchar[\msc@timer@opt{\msc@timer@opt[]}
}
% #1 - options or "l" or "r"
\def\msc@timer@opt[#1]{%parsing of [side] and [options]
  \ifx#1l \mscset{side=left}
  \else \ifx#1r \mscset{side=right}
    \else
      \pgfkeysactivatefamily{/msc/msccomment options}
      \pgfkeysfiltered{/msc,#1}
      \def\msc@options{#1}
     \fi
  \fi
  \pgfutil@ifnextchar[{\msc@timer@opt}{\msc@timer}
}
% #1 - label
% #2 - instance name
\def\msc@timer#1#2{
  \edef\msc@undefined{false}
  \edef\msc@instname{#2}
  \pgfkeysifdefined{/msc/instance/\msc@instname/no}{
    \IfStrEq{\mscget{side}}{left}{
      \edef\msc@node{msc@node\msc@instname @l\the\c@msclevelcnt}
     } {
      \edef\msc@node{msc@node\msc@instname @r\the\c@msclevelcnt}
    }
  }{
    \pgfutil@ifundefined{pgf@sh@ns@msc@node\msc@instname}{% neither instance name nor reference node
      \edef\msc@undefined{true}
      \msc@instundefinederr{\msc@instname}
    }
    {
      \edef\msc@node{msc@node\msc@instname|-msc@level\the\c@msclevelcnt}
    }
  }
  \IfStrEq{\msc@undefined}{false}{
    \IfStrEq{\mscget{side}}{left}{
      \def\msc@anchor{east}
      \edef\msc@timer@dist{-\mscget{self message width}}
      \edef\msc@label@dist{-\mscget{label distance}}
     } {
      \edef\msc@timer@dist{\mscget{self message width}}
      \def\msc@anchor{west}
      \edef\msc@label@dist{\mscget{label distance}}
    }
    \xdef\msc@tempb{[/msc,\msc@timertype={\mscget{timer width}},
              every timer, \msc@options]
              let \noexpand\p1 = (\msc@node)
              in (\noexpand\x1+\msc@timer@dist,\noexpand\y1)
              node [xshift=\msc@label@dist,/msc,anchor=\msc@anchor]{#1} to (\noexpand\x1,\noexpand\y1);
          }%use macro to expand parameters
    \end{pgfscope}
    \adddraw{#2}{\the\c@msclevelcnt}{\expandafter\draw\msc@tempb}
  }{
    \msc@instundefinederr{#2}\end{pgfscope}
  }
}
%\setstoptimer[placement]{name}{instance}[offset]
\def\setstoptimer{
 \begin{pgfscope}
  \def\msc@options{} \def\msc@timertype{setstoptimer style}
  \pgfutil@ifnextchar[\msc@fulltimer@opt{\msc@fulltimer@opt[]}
}
%\settimeout[placement]{name}{instance}[offset]
\def\settimeout{
 \begin{pgfscope}
  \def\msc@options{} \def\msc@timertype{settimeout style}
  \pgfutil@ifnextchar[\msc@fulltimer@opt{\msc@fulltimer@opt[]}
}

% #1 - options or "l" or "r"
\def\msc@fulltimer@opt[#1]{%parsing of [side] and [options]
  \ifx#1l \mscset{side=left}
  \else \ifx#1r \mscset{side=right}
    \else
      \pgfkeysactivatefamily{/msc/msccomment options}
      \pgfkeysfiltered{/msc,#1}
      \def\msc@options{#1}
     \fi
  \fi
  \pgfutil@ifnextchar[{\msc@fulltimer@opt}{\msc@fulltimer}
}
\def\msc@fulltimer#1#2{
  \xdef\msc@instname{#2}
  \def\msc@name{#1}
  \pgfutil@ifnextchar[{\msc@fulltimer@noopt}{\msc@fulltimer@noopt[\mscget{offset}]}
}
\def\msc@fulltimer@noopt[#1]{
  \edef\msc@undefined{false}
  \pgfkeysifdefined{/msc/instance/\msc@instname/no}{
    \IfStrEq{\mscget{side}}{left}{
      \edef\msc@node{msc@node\msc@instname @l}
     } {
      \edef\msc@node{msc@node\msc@instname @r}
    }
  }{
    \pgfutil@ifundefined{pgf@sh@ns@msc@node\msc@instname}{% neither instance name nor reference node
      \edef\msc@undefined{true}
      \msc@instundefinederr{\msc@instname}
    }
    {
      \edef\msc@node{msc@node\msc@instname|-msc@level}
    }
  }
  \IfStrEq{\msc@undefined}{false}{
%   \pgfkeysifdefined{/msc/instance/\msc@instname/no}{
    \msc@getlevel shift{#1}{\msc@level shift}{\msc@drawlevel}
    \IfStrEq{\mscget{side}}{left}{
      \edef\msc@mess@dist{-\mscget{self message width}}
      \edef\msc@label@dist{-\mscget{label distance}}
      \def\msc@anchor{east}
    }{
      \edef\msc@mess@dist{\mscget{self message width}}
      \edef\msc@label@dist{\mscget{label distance}}
      \def\msc@anchor{west}
    }
    \xdef\msc@tempb{[/msc,\msc@timertype={\msc@mess@dist}{\mscget{timer width}},
                    every timer,\msc@options]
         (\msc@node\the\c@msclevelcnt)
      node [xshift=\msc@label@dist+\msc@mess@dist,/msc,anchor=\msc@anchor]{\msc@name}
      to (\msc@node\msc@level shift);
    }
   \end{pgfscope}
   \adddraw{\expandafter\noexpand\msc@instname}{\expandafter\noexpand\msc@drawlevel}{\expandafter\draw\msc@tempb}
%    \edef\msc@drawlevel{0}
  }{
   \end{pgfscope}\msc@instundefinederr{\msc@instname}
  }
}
% \mscmark[position]{name}{instname}
\def\mscmark{
 \begin{pgfscope}
  \def\msc@options{}
  \pgfutil@ifnextchar[\msc@mark@opt{\msc@mark@opt[]}
}
\def\msc@mark@opt[#1]{%parsing of [side] and [options]
   \IfEqCase{#1}{%
     {l}{\mscset{side=left}}%
     {r}{\mscset{side=right}}%
     {t}{\mscset{position=above}}%
     {b}{\mscset{position=below}}%
     {tl}{\mscset{side=left,position=above}}%
     {tr}{\mscset{side=right,position=above}}%
     {bl}{\mscset{side=left,position=below}}%
     {br}{\mscset{side=right,position=below}}%
   }[%
    \mscset{#1}
    \def\msc@options{#1}
  ]
  \pgfutil@ifnextchar[{\msc@mark@opt}{\msc@mark}
}

\def\msc@mark#1#2{
  \def\msc@undefined{false}
  \pgfkeysifdefined{/msc/instance/#2/no}{
    \IfStrEq{\mscget{side}}{left}{
      \edef\msc@node{msc@node#2@l\the\c@msclevelcnt}
     } {
      \edef\msc@node{msc@node#2@r\the\c@msclevelcnt}
    }
  }{
    \pgfutil@ifundefined{pgf@sh@ns@msc@node#2}{% neither instance name nor reference node
      \edef\msc@undefined{true}
      \msc@instundefinederr{#2}
    }
    {
      \edef\msc@node{msc@node#2|-msc@level\the\c@msclevelcnt}
    }
  }
  \IfStrEq{\msc@undefined}{false}{
    \IfStrEq{\mscget{side}}{left}{
      \edef\msc@anchor@l{south east}
      \edef\msc@anchor@r{south west}
      \edef\msc@dist{-\mscget{mark distance}}
     } {
      \edef\msc@dist{\mscget{mark distance}}
      \edef\msc@anchor@l{south west}
      \edef\msc@anchor@r{south east}
    }
    \IfStrEq{\mscget{position}}{above}{
     \edef\msc@mark@ydist{0.5*\mscget{mark distance}}
    }{
     \IfStrEq{\mscget{position}}{below}{
       \edef\msc@mark@ydist{-0.5*\mscget{mark distance}}
     }
     {
       \IfStrEq{\mscget{position}}{mid}{
         \edef\msc@mark@ydist{0pt}
       }{%unknown
       }
     }
    }
    \xdef\msc@tempb{[/msc,mscdash,/tikz/line width=\mscget{line width}, every mscmark, \msc@options]
            (\msc@node)
            ++(\msc@dist,\msc@mark@ydist)
            node[anchor=\msc@anchor@l,inner sep=\mscget{label distance}, append after command={
              (\msc@node)--
              (\noexpand\tikzlastnode .\msc@anchor@l)--(\noexpand\tikzlastnode .\msc@anchor@r)
            }] {#1};
          }
    \end{pgfscope}
    \adddraw{#2}{\the\c@msclevelcnt}{\expandafter\draw\msc@tempb}
  }{}
}
% \measure(*)[placement]{name}{instance1}{instance2}[offset]
\def\measure{
 \begin{pgfscope}
  \def\msc@options{}
  \pgfutil@ifnextchar*{\msc@isstartrue\msc@measure@nostar}{\msc@isstarfalse\msc@measure@nostar*}
}
\def\msc@measure@nostar*{\pgfutil@ifnextchar[\msc@measure@opt{\msc@measure@opt[]}}
\def\msc@measure@opt[#1]{%parsing of [side] and [options]
  \ifx#1l \mscset{side=left}
  \else \ifx#1r \mscset{side=right}
    \else
      \mscset{#1}
      \def\msc@options{#1}
     \fi
  \fi
  \pgfutil@ifnextchar[{\msc@measure@opt}{\msc@measure@noopt}
}

\def\msc@measure@noopt#1#2#3{
  \def\msc@measure@name{#1}
  \xdef\msc@instnameI{#2}
  \xdef\msc@instnameII{#3}
   \pgfutil@ifnextchar[{\msc@measure@final}{\msc@measure@final[\mscget{offset}]}
}

\def\msc@measure@final[#1]{
  \pgfkeysifdefined{/msc/instance/\msc@instnameI/no}{
    \pgfkeysifdefined{/msc/instance/\msc@instnameII/no}{
      \msc@getlevel shift{#1}{\msc@level shift}{\msc@drawlevel}
      \ifmsc@isstar\def\msc@style{measure* style}\else\def\msc@style{measure style}\fi
      \IfStrEq{\mscget{side}}{left}{
        \edef\msc@nodeI{msc@node\msc@instnameI @l\the\c@msclevelcnt}
        \edef\msc@nodeII{msc@node\msc@instnameII @l\msc@level shift}
        \edef\msc@dist{-\mscget{measure distance}-\noexpand\noexpand\noexpand\msc@x+
          min(\noexpand\noexpand\noexpand\msc@x,\noexpand\noexpand\noexpand\msc@y)}
        \edef\msc@anchor{east}
       } {
        \edef\msc@nodeI{msc@node\msc@instnameI @r\the\c@msclevelcnt}
        \edef\msc@nodeII{msc@node\msc@instnameII @r\msc@level shift}
        \edef\msc@dist{\mscget{measure distance}-\noexpand\noexpand\noexpand\msc@x
          +max(\noexpand\noexpand\noexpand\msc@x,\noexpand\noexpand\noexpand\msc@y)}
        \edef\msc@anchor{west}
      }
      \xdef\msc@tempa{
        \noexpand\mscgetx{(\msc@nodeI)}{\noexpand\msc@x}
        \noexpand\mscgetx{(\msc@nodeII)}{\noexpand\msc@y}
        \noexpand\pgfmathparse{\msc@dist}
        \noexpand\edef\noexpand\msc@dist{\noexpand\pgfmathresult}
      }
      \xdef\msc@tempb{[/msc,draw, mscdash,
        \msc@style={\noexpand\msc@dist pt}{\mscget{measure symbol width}}, every measure,
        \msc@options] (\msc@nodeI) to
          node[/msc,anchor=\msc@anchor, inner sep=\mscget{label distance}, every measure, \msc@options]{\unexpanded\expandafter{\msc@measure@name}}
          (\msc@nodeII);
%         \noexpand\path ($(a) !\mscget{pos}! (b)$)
%            node[/msc,anchor=\msc@anchor, inner sep=\mscget{label distance}, every measure, \msc@options]{text};
            }
      \end{pgfscope}
      \addDdraw{\msc@instnameI}{\msc@instnameII}{\expandafter\noexpand\msc@drawlevel}{\expandafter\noexpand\msc@tempa}
      \addDdraw{\msc@instnameI}{\msc@instnameII}{\expandafter\noexpand\msc@drawlevel}{\expandafter\draw\msc@tempb}
    }{
     \msc@instundefinederr{\msc@instnameII}\end{pgfscope}
   }
  }{
    \msc@instundefinederr{\msc@instnameI}\end{pgfscope}
  }
}
%\measurestart(*)[placement]{name}{instance}{gate}
\def\measurestart{
 \begin{pgfscope}
  \def\msc@options{}
  \def\msc@sign{}
  \pgfutil@ifnextchar*{\edef\msc@style{measurestart* style}\msc@measuregap@nostar}{\edef\msc@style{measurestart style}\msc@measuregap@nostar*}
}
% \measureend(*)[placement]{name}{instance}{gate}
\def\measureend{
 \begin{pgfscope}
  \def\msc@options{}
  \def\msc@sign{-1*}
  \pgfutil@ifnextchar*{\edef\msc@style{measurestart* style}\msc@measuregap@nostar}{\edef\msc@style{measurestart style}\msc@measuregap@nostar*}
}
\def\msc@measuregap@nostar*{\pgfutil@ifnextchar[\msc@measuregap@opt{\msc@measuregap@opt[]}}
\def\msc@measuregap@opt[#1]{%parsing of [side] and [options]
  \ifx#1l \mscset{side=left}
  \else \ifx#1r \mscset{side=right}
    \else
      \mscset{#1}
      \def\msc@options{#1}
     \fi
  \fi
  \pgfutil@ifnextchar[{\msc@measuregap@opt}{\msc@measuregap@noopt}
}

\def\msc@measuregap@noopt#1#2#3{
  \edef\msc@text{#1}
  \gdef\msc@instname{#2}
  \edef\msc@gate{#3}
   \pgfutil@ifnextchar[{\msc@measuregap@final}{\msc@measuregap@final[\mscget{offset}]}
}

\def\msc@measuregap@final[#1]{
  \pgfkeysifdefined{/msc/instance/\msc@instname/no}{
    \msc@getlevel shift{\msc@sign#1}{\msc@level shift}{\msc@drawlevel}
    \IfStrEq{\mscget{side}}{left}{
      \edef\msc@nodeI{msc@node\msc@instname @l\the\c@msclevelcnt}
      \edef\msc@nodeII{msc@node\msc@instname @l\msc@level shift}
      \edef\msc@dist{-\mscget{measure distance}}
      \edef\msc@anchor{east}
     } {
      \edef\msc@nodeI{msc@node\msc@instname @r\the\c@msclevelcnt}
      \edef\msc@nodeII{msc@node\msc@instname @r\msc@level shift}
      \edef\msc@dist{\mscget{measure distance}}
      \edef\msc@anchor{west}
    }
    \xdef\msc@tempb{[/msc,mscdash,draw,
      \msc@style={\msc@dist}{\mscget{measure symbol width}}, every measure,
      \msc@options] (\msc@nodeI) to node[/msc,anchor=\msc@anchor, inner
      sep=\mscget{label distance}, every measure, \msc@options]{\msc@text} (\msc@nodeII);
      \noexpand\path (b) node[/msc,anchor=\msc@anchor, inner sep=\mscget{label distance}, every measure, \msc@options]{\msc@gate};
          }
    \end{pgfscope}
    \adddraw{\msc@instname}{\expandafter\noexpand\msc@drawlevel}{\expandafter\draw\msc@tempb}
  }{
  \msc@instundefinederr{\msc@instname}\end{pgfscope}
 }
}

% \lost[side]{name}[label position]{gate}{instance}[pos]
\def\lost{
 \begin{pgfscope}
  \def\msc@options{}
  \def\msc@style{lost style}
  \pgfutil@ifnextchar[{\msc@lost@opt}{\msc@lost@opt[]}
}
% \found[pos]{name}[label position]{gate}{instance}[placement]
\def\found{
 \begin{pgfscope}
  \def\msc@options{}
  \def\msc@style{found style}
  \pgfutil@ifnextchar[{\msc@lost@opt}{\msc@lost@opt[]}
}
\def\msc@lost@opt[#1]#2{
  \ifx#1l \mscset{side=left}
  \else \ifx#1r \mscset{side=right}
    \else
      \mscset{#1}
      \def\msc@options{#1}
     \fi
  \fi
  \def\msc@text{#2}
  \pgfutil@ifnextchar[{\msc@lost@noopt}{\msc@lost@noopt[]}
}
\def\msc@lost@noopt[#1]#2#3{
  \mscset{label position=above}
  \expandafter\ifx#1b \mscset{label position=below} \fi
  \def\msc@gate{#2}
  \xdef\msc@instname{#3}
  \pgfutil@ifnextchar[{\msc@lost@final}{\msc@lost@final[\mscget{pos}]}
}
\def\msc@lost@final[#1]{
  \def\msc@undefined{false}
  \pgfkeysifdefined{/msc/instance/\msc@instname/no}{
    \IfStrEq{\mscget{side}}{left}{
      \edef\msc@node{msc@node\msc@instname @l\the\c@msclevelcnt}
     } {
      \edef\msc@node{msc@node\msc@instname @r\the\c@msclevelcnt}
    }
  }{
    \pgfutil@ifundefined{pgf@sh@ns@msc@node\msc@instname}{% neither instance name nor reference node
      \edef\msc@undefined{true}
      \msc@instundefinederr{\msc@instname}
    }
    {
      \edef\msc@node{msc@node\msc@instname|-msc@level\the\c@msclevelcnt}
    }
  }
  \IfStrEq{\msc@undefined}{false}{
    \mscset{pos=#1}
    \IfStrEq{\mscget{side}}{left}{
      \edef\msc@dist{-\mscget{self message width}}
      \edef\msc@anchor{east}
     } {
      \edef\msc@dist{\mscget{self message width}}
      \edef\msc@anchor{west}
    }
    \xdef\msc@tempb{[/msc,draw,
      \msc@style={2*\mscget{lost symbol radius}}, every lostfound,
      \msc@options] (\msc@node) to node[/msc,\mscget{label position}, inner
      sep=\mscget{label distance}, every lostfound, \msc@options]{\unexpanded\expandafter{\msc@text}}
      ++(\msc@dist,0);
      \noexpand\path(\msc@node) ++(\msc@dist,0)
      node[/msc,above,anchor=\msc@anchor,%
      inner sep=\mscget{label distance}, every lostfound, \msc@options]{\msc@gate};
      }
    \end{pgfscope}
    \adddraw{\msc@instname}{\the\c@msclevelcnt}{\expandafter\draw\msc@tempb}
  }{}
}

% \condition puts a condition symbol over the given instances. The
% starred version adjusts the width and the height of the condition symbol.
% #1: name to be put inside the condition symbol
% #2: comma-separated list of instance nicknames, such that:
%     - The first instance nickname is supposed to be the leftmost
%       instance of the condition
%     - The last instance nickname is supposed to be the rightmost
%       instance of the condition
% \condition(*)[options]{text}{instancelist}
\def\condition{
  \advance\c@condition by1\relax
 \begin{pgfscope}
   \edef\msc@shape{condition shape}
  \pgfutil@ifnextchar*{\msc@isstartrue\msc@cond@star}{\msc@isstarfalse\msc@cond@star*}
}
\def\ncondition{
 \begin{pgfscope}
   \edef\msc@shape{ncondition shape}
  \pgfutil@ifnextchar*{\msc@isstartrue\msc@cond@star}{\msc@isstarfalse\msc@cond@star*}
}
% \ncondition(*)[options]{text}{instancelist}
\def\msc@cond@star*{
  \pgfutil@ifnextchar[{\msc@condition}{\msc@condition[]}
}
\newif\ifmsc@isfirst
\def\msc@condition[#1]#2#3{
 \mscset{inner sep=\mscget{label distance},#1}
  \msc@isfirsttrue
  \@for\msc@arg:=#3\do{%
    \pgfkeysifdefined{/msc/instance/\msc@arg/no}{
      \ifmsc@isfirst%first instance in the list
        \mscgetx{(msc@node\msc@arg @l0)}{\msc@minx}
        \mscgetx{(msc@node\msc@arg @r0)}{\msc@maxx}
        \mscgety{(msc@level\the\c@msclevelcnt)}{\msc@y}
      \else
        \mscgetx{(msc@node\msc@arg @r0)}{\msc@x}
        \pgfmathparse{max(\msc@x,\msc@maxx)}
        \edef\msc@maxx{\pgfmathresult pt}
        \mscgetx{(msc@node\msc@arg @l0)}{\msc@x}
        \pgfmathparse{min(\msc@x,\msc@minx)}
        \edef\msc@minx{\pgfmathresult pt}
      \fi
      \msc@isfirstfalse
      \xdef\msc@instname{\msc@arg}
    }{
      \msc@instundefinederr{\msc@arg}
    }
  }
 \ifmsc@isfirst \else%there are proper instances
   \pgfmathparse{2*\mscget{condition overlap}+\msc@maxx-\msc@minx}
   \edef\msc@width{\pgfmathresult pt}
   \ifmsc@isstar
     \def\msc@tempr{}
   \else
     %\msc@savebox{\parbox{\msc@width}{#2}}
     \edef\msc@tempr{%text depth={\the\dp\msc@box},
                    % text height={{\the\ht\msc@box+\the\dp\msc@box}},
                    align=center, text width=\msc@width-2*\mscget{label distance},}
   \fi
   \def\aa{aeee}
   \xdef\msc@tempb{[/msc, draw, anchor=north,shape=\msc@shape,
     \msc@tempr
     inner sep=\mscget{label distance},
     minimum height=\mscget{condition height},
     minimum width=\msc@width,
     every condition,/tikz/line width=\mscget{line width}, #1](msc@condition@\the\c@condition)
     at ({(\msc@maxx+\msc@minx)/2},\msc@y) {\unexpanded\expandafter{#2}};
   }
 \fi
 \end{pgfscope}
 \adddraw{\msc@instname}{\the\c@msclevelcnt}{\expandafter\node\msc@tempb }
  \@for\msc@args:=#3\do{%
    \edef\msc@tempa{\noexpand\mscgety{(msc@condition@\the\c@condition.south)}{\noexpand\msc@y}
      \noexpand\msc@setlastlevel{\msc@args}{\noexpand\msc@y}}
%     \show\msc@tempa
    \adddraw{\msc@args}{\the\c@msclevelcnt}{\msc@tempa}
  }
}
% \order[side]{sender}{receiver}[level shift]
\def\order{
  \begin{pgfscope}
  \def\msc@options{}
  \pgfutil@ifnextchar[{\msc@order@opt}{\msc@order@opt[]}
}
\def\msc@order@opt[#1]{
  \ifx#1l \mscset{side=left}
  \else \ifx#1r \mscset{side=right}
    \else
      \mscset{#1}
      \def\msc@options{#1}
     \fi
  \fi
  \pgfutil@ifnextchar[{\msc@order@opt}{\msc@order@noopt}
}
\def\msc@order@noopt#1#2{
  \xdef\msc@sender{#1}
  \xdef\msc@receiver{#2}
  \pgfutil@ifnextchar[{\msc@order}{\msc@order[\mscget{level shift}]}
}
\def\msc@order[#1]{
  \pgfkeysifdefined{/msc/instance/\msc@receiver/no}{
    \pgfkeysifdefined{/msc/instance/\msc@sender/no}{
      \msc@getlevel shift{#1}{\msc@level shift}{\msc@tempa}
      \ifx\msc@sender\msc@receiver  %self message
        \IfStrEq{\mscget{side}}{left}{
          \def\msc@dir{l}
          \edef\msc@dist{-\mscget{self message width}}
        }{
          \def\msc@dir{r}
          \edef\msc@dist{\mscget{self message width}}
        }
        \xdef\msc@tempb{[/msc, order loop={\msc@dist},
                 every order, \msc@options]
                 (msc@node\msc@sender @\msc@dir\the\c@msclevelcnt) to
                 (msc@node\msc@receiver @\msc@dir\msc@level shift);
        }
      \else
        \ifnum\mscget{instance/\msc@sender/no}\expandafter&lt;\mscget{instance/\msc@receiver/no}\relax
              \def\msc@ldir{r}
              \def\msc@rdir{l}
        \else
              \def\msc@ldir{l}
              \def\msc@rdir{r}
        \fi
        \xdef\msc@tempb{[/msc,order,every order,\msc@options]
                 (msc@node\msc@sender @\msc@ldir\the\c@msclevelcnt) to
                 (msc@node\msc@receiver @\msc@rdir\msc@level shift);
        }
      \fi
      \end{pgfscope}
      \addDdraw{\msc@sender}{\msc@receiver}{\msc@tempa}{\expandafter\draw\msc@tempb}
    }{\msc@instundefinederr{\msc@sender}\end{pgfscope}}
  }{\msc@instundefinederr{\msc@receiver}\end{pgfscope}}
}

% update the lastlevel for a given instance
% #1 name of the instance
% #2 level number
\def\msc@updatelastlevel#1#2{
  \msc@StrEqEither{#1}{envright}{envleft} {}{
    \path let \p1 = (msc@lastlevel#1), \p2 = (msc@level#2)
      in coordinate (msc@lastlevel#1) at (\x1,{min(\y1,\y2)});
  }
}
% set the lastlevel for a given instance
% #1 name of the instance
% #2 new height
\def\msc@setlastlevel#1#2{
  \msc@StrEqEither{#1}{envright}{envleft} {}{
    \draw let \p1 = (msc@lastlevel#1) in coordinate (msc@lastlevel#1)
    at (\x1,{min(\y1,#2)});
  }
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  CO-REGIONS
%
% \coregionstart starts a coregion on instance #1 (nickname) in the current level.
\def\coregionstart{\pgfutil@ifnextchar[{\msc@coreg}{\msc@coreg[]}}
\def\msc@coreg[#1]#2{
  \regionstart[#1]{coregion}{#2}}
% \coregionend ends a coregion on instance #1 (nickname) in the current level.
\def\coregionend#1{\regionend{#1}}%
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% REGIONS (normal, coregion, suspension, and activation)
%
%

% define the begining of a region on the instance line
%\regionstart[options]{type}{instname}
% instance/#2/region/.initial=line, %possible % values:normal,coregion,suspension,activation
\def\regionstart{\pgfutil@ifnextchar[\msc@regionstart{\msc@regionstart[]}}
\def\msc@regionstart[#1]#2#3{
  \begin{pgfscope}
    \mscset{#1}
    \xdef\msc@tempa{\mscget{region width}}
  \end{pgfscope}
  \pgfkeysifdefined{/msc/instance/#3/no}{
    \msc@StrEqEither{\mscget{instance/#3/region}}{normal}{seminormal}{
      \msc@drawinstanceline{#2}{\the\c@msclevelcnt}
      \IfEqCase{#2} {{coregion}{} {activation}{} {suspension}{}}
         [\msc@unknownregionstyleerr{#2}]
      \mscset{instance/#3/region={#2},
              instance/#3/region level/.expand once={\the\c@msclevelcnt},
              instance/#3/region width/.expand once=\msc@tempa}%
       \msc@regbar{#3}{\the\c@msclevelcnt}
    }
    {msc@regionstartederr{#3}{\mscget{instance/#3/region}}}
  }
  {\msc@instundefinederr{#3}}
}
%helper function to draw region horizontal bar(s)
% #1 instname
% #2 level
\def\msc@regbar#1#2{
  \xdef\msc@temp@body{}
  \edef\msc@region{\mscget{instance/#1/region}}
  \pgfpointanchor{msc@level#2}{center}
  \edef\msc@regbar@tempb{\the\pgf@y}
  \pgfpointanchor{msc@lastlevel#1}{center}
  \pgfmathparse{\msc@regbar@tempb-\the\pgf@y}
  \ifnum0&lt;\pgfmathresult\relax
  \else
    \IfStrEq{\mscget{instance/#1/type}}{fat}{
      \IfStrEq{\msc@region}{coregion}{
        \xdef\msc@temp@body{
            [/msc,/tikz/line width=\mscget{line width}, draw, every region,every
            coregion] let \noexpand\p1=(msc@node#1@l#2) in
          (\noexpand\x1-\mscget{instance/#1/region width}/2-\mscget{line width}/2,\noexpand\y1) --
          (\noexpand\x1+\mscget{instance/#1/region width}/2+\mscget{line
            width}/2,\noexpand\y1);
          \noexpand\draw [/msc,/tikz/line width=\mscget{line width}, every region,every
            coregion] let \noexpand\p1=(msc@node#1@r#2) in
          (\noexpand\x1-\mscget{instance/#1/region width}/2-\mscget{line width}/2,\noexpand\y1) --
          (\noexpand\x1+\mscget{instance/#1/region width}/2+\mscget{line width}/2,\noexpand\y1);
        }
      }{
        \xdef\msc@temp@body{
          [/msc,/tikz/line width=\mscget{line width}, draw, every region,every \msc@region] let
            \noexpand\p1=(msc@node#1@l#2), \noexpand\p2=(msc@node#1@r#2) in
           (\noexpand\x1-\mscget{line width}/2,\noexpand\y1)--(\noexpand\x2+\mscget{line width}/2,\noexpand\y2);
        }
      }
    }{
      \IfStrEq{\msc@region}{coregion}{
        \xdef\msc@temp@body{
           [/msc,/tikz/line width=\mscget{line width}, draw, every region,every coregion] let
            \noexpand\p1=(msc@node#1@l#2) in
          (\noexpand\x1-\mscget{instance/#1/region width}/2-\mscget{line width}/2,\noexpand\y1) --
          (\noexpand\x1+\mscget{instance/#1/region width}/2+\mscget{line width}/2,\noexpand\y1);
        }
      }{
        \xdef\msc@temp@body{
              [/msc,/tikz/line width=\mscget{line width}, draw, every region, every \msc@region]
              let
              \noexpand\p1=(msc@node#1@l#2), \noexpand\p2=(msc@node#1@r#2) in
             (\noexpand\x1-\mscget{line width}/2,\noexpand\y1)--(\noexpand\x2+\mscget{line width}/2,\noexpand\y2);
        }
      }
    }
%     \show\msc@temp@body
    \adddraw{#1}{\the\c@msclevelcnt}{\expandafter\path\msc@temp@body}
    \adddraw{#1}{\the\c@msclevelcnt}{\mscgety{(msc@lastlevel#1)}{\msc@yo}\msc@setlastlevel{#1}{\msc@yo-\mscget{line width}/2}}
  \fi
}
% draw the instance line with the region
% #1 instname
% #2 level
\def\msc@regbody#1#2{
  \xdef\msc@temp@body{;}
  \pgfpointanchor{msc@level#2}{center}
  \edef\msc@regbody@tempb{\the\pgf@y}
  \pgfpointanchor{msc@lastlevel#1}{center}
  \pgfmathparse{\msc@regbody@tempb-\the\pgf@y}
  \ifnum0&lt;\pgfmathresult\relax
  \else
    \IfEqCase{\mscget{instance/#1/region}}{
      {coregion}{
        \IfStrEq{\mscget{instance/#1/type}}{fat}{
          \xdef\msc@temp@body{
             [/msc,/tikz/line width=\mscget{line width}, draw, mscdash, every region, every coregion]
                let \noexpand\noexpand\noexpand\p1=(msc@node#1@r#2), \noexpand\noexpand\noexpand\p2=(msc@lastlevel#1) in
                (\noexpand\noexpand\noexpand\x1,\noexpand\noexpand\noexpand\y2)--
                (\noexpand\noexpand\noexpand\x1,{min(\noexpand\noexpand\noexpand\y2,\noexpand\noexpand\noexpand\y1)});
          }
        }{\xdef\msc@temp@body{;}}
        \xdef\msc@temp@body{
          [/msc,/tikz/line width=\mscget{line width}, draw, mscdash, every region, every coregion]
             let \noexpand\p1=(msc@node#1@l#2), \noexpand\p2=(msc@lastlevel#1) in
               (\noexpand\x1,\noexpand\y2)--(\noexpand\x1,{min(\noexpand\y2,\noexpand\y1)});\noexpand\path\msc@temp@body
       }
      }%
      {activation}{
        \xdef\msc@temp@body{
          [/msc,fill=lightgray,/tikz/line width=\mscget{line width},every region, every activation]
          (msc@node#1@l#2|-msc@lastlevel#1) rectangle(msc@node#1@r#2);
          \noexpand\draw[/msc,/tikz/line width=\mscget{line width},every region, every activation]
          (msc@node#1@l#2) -- (msc@node#1@l#2|-msc@lastlevel#1)
          (msc@node#1@r#2) -- (msc@node#1@r#2|-msc@lastlevel#1);
        }
      }%
      {suspension}{
        \xdef\msc@temp@body{
          [/msc,draw,suspension dash,
          /tikz/line width=\mscget{line width},every region, every activation]
          (msc@node#1@r#2)--(msc@node#1@r#2|-msc@lastlevel#1)
          (msc@node#1@l#2)--(msc@node#1@l#2|-msc@lastlevel#1);
        }
      }%
    }[]
    \adddraw{#1}{\the\c@msclevelcnt}{\expandafter\path\msc@temp@body}
  \fi
}
% define the end of region
%\regionend{instname}
\def\regionend#1{
  \pgfkeysifdefined{/msc/instance/#1/no}{
    \edef\msc@region{\mscget{instance/#1/region}}
    \IfStrEq{\msc@region}{normal}{
      \msc@regionnotstartederr{#1}
    }
    \msc@regbody{#1}{\the\c@msclevelcnt}
    \msc@regbar{#1}{\mscget{instance/#1/region level}}
    \msc@regbar{#1}{\the\c@msclevelcnt}
    \adddraw{#1}{\the\c@msclevelcnt}{\msc@updatelastlevel{#1}{\the\c@msclevelcnt}}
    \msc@StrEqEither{\msc@region}{suspension}{activation}{
      \mscset{instance/#1/region=seminormal}
    }{\mscset{instance/#1/region=normal}}
  }
  {
    \msc@instundefinederr{#1}
  }
}
%macro stores first character in \msc@fst and last character in \msc@lst
\def\msc@fl#1{\msc@flx#1\empty\empty\empty}
\def\msc@flx#1#2#3\empty{%
\edef\msc@fst{#1}%
 \edef\msc@cdar{#2}%
 \edef\msc@cddr{#3}%
  \ifx\msc@cddr\empty
    \let\msc@lst\msc@cdar
  \else
     \expandafter\msc@flxx
   \fi
  #3}
\def\msc@flxx#1#2\empty{%
 \edef\msc@car{#1}%
  \ifx\msc@car\empty
  \else
     \let\msc@lst\msc@car
     \expandafter\msc@flxx
   \fi
  #2\empty}
%\referencestart[options][lo][ro]{nickname}{text}{leftinstance}{rightinstance}
\def\referencestart{
  \begin{pgfscope}\gdef\msc@options{}
  \pgfutil@ifnextchar[\msc@refstartlo{\msc@refstartloro}}
\def\msc@refstartloro{
  \edef\msc@lo{\mscget{left reference overlap}}
  \edef\msc@ro{\mscget{right reference overlap}}
  \msc@refstart
}
\def\msc@refstartlo[#1]{
  \expandafter\expandafter\expandafter\msc@fl\expandafter{#1}
  \msc@caseFiveEither{\msc@fst}{1}{2}{3}{4}{5}{
    \edef\msc@lo{#1} \pgfutil@ifnextchar[\msc@refstartro{\msc@refstartro[\mscget{right reference overlap}]}
  }{
    \msc@caseFiveEither{\msc@fst}{6}{7}{8}{9}{0}{
      \edef\msc@lo{#1} \pgfutil@ifnextchar[\msc@refstartro{\msc@refstartro[\mscget{right reference overlap}]}
    }{
      \msc@StrEqEither{\msc@fst}{-}{.}{
        \edef\msc@lo{#1} \pgfutil@ifnextchar[\msc@refstartro{\msc@refstartro[\mscget{right reference overlap}]}
      }{
        \mscset{#1}
        \xdef\msc@options{#1}
        \pgfutil@ifnextchar[\msc@refstartlo{\msc@refstartloro}
      }
    }
  }
}
\def\msc@refstartro[#1]{
  \edef\msc@ro{#1}\msc@refstart
}
\def\msc@refstart#1#2#3#4{
  \pgfkeysifdefined{/msc/instance/#3/no}{
    \pgfkeysifdefined{/msc/instance/#4/no}{
        \path[draw] (msc@level\the\c@msclevelcnt-|msc@node#3@l0) ++(-\msc@lo,0) coordinate
       (msc@node#1left)
       (msc@level\the\c@msclevelcnt-|msc@node#4@r0) ++(\msc@ro,0) coordinate
       (msc@node#1right);
      \end{pgfscope}
      \msc@cover{#3}{#4}{+}
      \mscset{
        reference/#1/options/.style/.expanded=\msc@options,
        reference/#1/left/.initial=#3,
        reference/#1/text/.initial={#2},
        reference/#1/right/.initial=#4
      }
    }{
      \end{pgfscope}\msc@instundefinederr{#4}
    }
  }{
    \end{pgfscope}\msc@instundefinederr{#3}
  }
}
\def\msc@cover#1#2#3{
  \pgfmathparse{\mscget{instance/#2/cover} #3 1}
  \mscset{instance/#2/cover/.expand once=\pgfmathresult}
  \IfStrEq{#1}{#2}{}{
    \ifnum0&lt;\mscget{instance/\msc@inst@name/no}
      \msc@previousinstance{#2}
      \msc@cover{#1}{\msc@inst@name}{#3}
      \msc@regbody{\msc@inst@name}{\the\c@msclevelcnt}
    \else
    \fi
  }
}
\def\referenceend#1{
  \pgfkeysifdefined{/msc/reference/#1/left}{%calculating framearch
    \mscgetx{(msc@node#1left)}{\msc@xa}
    \mscgetx{(msc@node#1right)}{\msc@xb}
    \mscgety{(msc@node#1left)}{\msc@yb}
    \mscgety{(msc@level\the\c@msclevelcnt)}{\msc@ya}
    \pgfmathparse{0.25/2 *min(\msc@xb-\msc@xa,\msc@yb-\msc@ya)}
    \edef\msc@tempa{\pgfmathresult}
    \msc@cover{\mscget{reference/#1/left}}{\mscget{reference/#1/right}}{-}
    \node[/msc,fit={(msc@node#1left) (msc@node#1right)
      (msc@node#1right|-msc@level\the\c@msclevelcnt)},
      draw,rectangle, rounded corners=\msc@tempa pt, inner sep=0,/tikz/line
      width=\mscget{line width},every reference,
      /msc/reference/#1/options
      ]{\mscget{reference/#1/text}};
   }{
    \msc@refundefinederr{#1}
   }
}
%\inlinestart[options][lo][ro]{nickname}{text}{leftinstance}{rightinstance}
\def\inlinestart{
  \begin{pgfscope}
  \gdef\msc@options{}
  \pgfutil@ifnextchar[\msc@inlstartlo{\msc@inlstartloro}
}
\def\msc@inlstartloro{
  \edef\msc@lo{\mscget{left inline overlap}}
  \edef\msc@ro{\mscget{right inline overlap}}
  \msc@inlstart
}

\def\msc@inlstartlo[#1]{
  \expandafter\expandafter\expandafter\msc@fl\expandafter{#1}
  \msc@caseFiveEither{\msc@fst}{1}{2}{3}{4}{5}{
    \edef\msc@lo{#1}
    \pgfutil@ifnextchar[\msc@inlstartro{\msc@inlstartro[\mscget{right inline overlap}]}
  }{
    \msc@caseFiveEither{\msc@fst}{6}{7}{8}{9}{0}{
      \edef\msc@lo{#1} \pgfutil@ifnextchar[\msc@inlstartro{\msc@inlstartro[\mscget{right inline overlap}]}
    }{
      \msc@StrEqEither{\msc@fst}{-}{.}{
        \edef\msc@lo{#1}
        \pgfutil@ifnextchar[\msc@inlstartro{\msc@inlstartro[\mscget{right inline overlap}]}
      }{
        \mscset{#1}
        \xdef\msc@options{#1}
        \pgfutil@ifnextchar[\msc@inlstartlo{\msc@inlstartloro}
      }
    }
  }
}
\def\msc@inlstartro[#1]{
  \edef\msc@ro{#1}\msc@inlstart
}
%msc@inlstart{nickname}{text}{leftinstance}{rightinstance}
\def\msc@inlstart#1#2#3#4{
  \pgfkeysifdefined{/msc/instance/#3/no}{
    \pgfkeysifdefined{/msc/instance/#4/no}{
      \path[draw] (msc@level\the\c@msclevelcnt-|msc@node#3@l0) ++(-\msc@lo,0) coordinate
        (msc@node#1left)
       (msc@level\the\c@msclevelcnt-|msc@node#4@r0) ++(\msc@ro,0) coordinate
       (msc@node#1right);
      \end{pgfscope}
      \mscset{
        inline/#1/options/.style/.expanded=\msc@options,
        inline/#1/left/.initial={#3},
        inline/#1/text/.initial={#2}
      }
    }{
      \end{pgfscope}\msc@instundefinederr{#4}
    }
  }{
    \end{pgfscope}\msc@instundefinederr{#3}
  }
}
%\inlineseparator[options]{nickname}
\def\inlineseparator{
  \begin{pgfscope}
  \pgfutil@ifnextchar[\msc@inlseparator{\msc@inlseparator[]}
}
\def\msc@inlseparator[#1]#2{
  \pgfkeysifdefined{/msc/inline/#2/left}{
    \mscset{#1}
    \end{pgfscope}
    \path[/msc,draw, mscdash,
    /tikz/line width=\mscget{line width},
    dash phase=2pt,
    every inline,inline/#2/options,#1]
    (msc@node#2left|-msc@level\the\c@msclevelcnt)--(msc@node#2right|-msc@level\the\c@msclevelcnt);
   }{
    \msc@inlundefinederr{#2}
    \end{pgfscope}
   }
}
%\inlineend{nickname}
\def\inlineend{
  \pgfutil@ifnextchar*{\msc@isstartrue\msc@inlineend}{\msc@isstarfalse\msc@inlineend*}
}
\def\msc@inlineend*#1{
  \pgfkeysifdefined{/msc/inline/#1/text}{
    \path[/msc,draw,
    /tikz/line width=\mscget{line width},
    every inline,inline/#1/options]
    (msc@node#1left) node[/msc,draw,chamfered rectangle,
    chamfered rectangle corners=south east,
    chamfered rectangle xsep=\mscget{label distance}/2,
    chamfered rectangle ysep=\mscget{label distance}/2,
    inner sep=\mscget{label distance}/4,
    xshift=-\mscget{line width}/2, yshift=\mscget{line width}/2,
    anchor=north west,inline/#1/options](a)
    {\mscget{inline/#1/text}}
    (msc@node#1left|-msc@level\the\c@msclevelcnt)++(0,-\mscget{line width}/2)
    --(msc@node#1left)--(msc@node#1right)--
    (msc@node#1right|-msc@level\the\c@msclevelcnt)--++(0,-\mscget{line width}/2);
    \ifmsc@isstar
      \inlineseparator{#1}
    \else
      \inlineseparator[solid]{#1}
    \fi
   }{
    \msc@refundefinederr{#1}
   }
}
%\gate(*)[options][hpos][vpos]{gatename}{instname}
\def\gate{
  \begin{pgfscope}
  \def\msc@options{}
  \pgfutil@ifnextchar*{\msc@isstartrue\msc@gate@star}{\msc@isstarfalse\msc@gate@star*}
}
\def\msc@gate@star*{
  \pgfutil@ifnextchar[{\msc@gate@opt}{\msc@gate@opt[]}
}
\def\msc@gate@opt[#1]{
  \IfStrEq{#1}{l}{\mscset{side=left} \pgfutil@ifnextchar[\msc@gate{\msc@gate[]}
  }{
    \IfStrEq{#1}{r}{\mscset{side=right}\pgfutil@ifnextchar[\msc@gate{\msc@gate[]}
    }{
      \mscset{#1}
      \def\msc@options{#1}
      \pgfutil@ifnextchar[\msc@gate@opt{\msc@gate[]}
    }
  }
}
\def\msc@gate[#1]#2#3{
  \def\msc@undefined{false}
  \ifx#1c \mscset{position=mid} \else
  \ifx#1b \mscset{position=below} \else
  \ifx#1t \mscset{position=above} \fi \fi \fi
  \pgfkeysifdefined{/msc/instance/#3/no}{%instance name
    \IfStrEq{\mscget{side}}{left}{
      \edef\msc@node{msc@node#3@l\the\c@msclevelcnt}
    }{
      \edef\msc@node{msc@node#3@r\the\c@msclevelcnt}
    }
  }{
    \pgfutil@ifundefined{pgf@sh@ns@msc@node#3}{% neither instance name nor reference node
      \def\msc@undefined{true}
      \msc@instundefinederr{#3}
    }
    {
      \edef\msc@node{msc@node#3|-msc@level\the\c@msclevelcnt}
    }
  }
  \IfStrEq{\msc@undefined}{false}{
    \ifmsc@isstar
      \xdef\msc@tempb{[fill,\msc@options] (\msc@node)
        node[\mscget{position}
        \mscget{side}]{\unexpanded\expandafter{#2}} circle (\mscget{gate symbol radius});}
      \edef\msc@tempa{\noexpand\noexpand\noexpand\path[fill,line width=0pt](\msc@node) circle (\mscget{gate symbol radius});}
    \else
      \xdef\msc@tempb{[\msc@options] (\msc@node) node[\mscget{position} \mscget{side}]{\unexpanded\expandafter{#2}};}
    \fi
  }{}
  \end{pgfscope}
  \adddraw{#3}{\the\c@msclevelcnt}{\expandafter\path\msc@tempb}
}

\def\inststop{\stop*}%old name of command
%\stop(*)[options]{instancename}
\def\stop{\pgfutil@ifnextchar*{\msc@isstartrue\msc@stop@nostar}{\msc@isstarfalse\msc@stop@nostar*}}
\def\msc@stop@nostar*{\pgfutil@ifnextchar[\msc@stop{\msc@stop[]}}
\def\msc@stop[#1]#2{
  \pgfkeysifdefined{/msc/instance/#2/no}{
    \IfStrEq{on}{\mscget{instance/#2/status}}{
      \msc@global@set{instance/#2/status=off}
      \begin{pgfscope}
      \mscset{#1}
      \ifmsc@isstar \mscset{instance end=foot} \fi
      \IfStrEq{\mscget{instance end}}{foot}{
        \xdef\msc@tempb{[/msc,fill=\mscget{draw foot},/tikz/line width=\mscget{line width}, every instance foot,#1]
          (msc@lastlevel#2-|msc@node#2.east)
          ++(0,-\mscget{foot height}) rectangle
          (msc@lastlevel#2-|msc@node#2.west)
          (msc@lastlevel#2-|msc@node#2.south)
          ++(0,-\mscget{foot height})
          coordinate (msc@foot#2);
        }
      }{
        \xdef\msc@tempb{[/msc,draw=\mscget{draw foot}, /tikz/line width=\mscget{line width},
          every instance foot,#1]
          (msc@node#2@l\the\c@msclevelcnt) ++(-\mscget{line width}/2,0)--
          ($(msc@node#2@l\the\c@msclevelcnt)!0.5!(msc@node#2@r\the\c@msclevelcnt)$)
          coordinate (msc@foot#2)
          ++(\mscget{stop width}/2,\mscget{stop width}/2)
          -- ++(-\mscget{stop width},-\mscget{stop width})
          ++(0,\mscget{stop width})
          -- ++(\mscget{stop width},-\mscget{stop width})
          ++(-\mscget{stop width}/2,\mscget{stop width}/2)
          -- (msc@node#2@r\the\c@msclevelcnt)
          --++(\mscget{line width}/2,0);
        }
      }
      \end{pgfscope}
      \adddraw{#2}{\the\c@msclevelcnt}{\expandafter\path\msc@tempb}
    }{}
  }{\msc@instundefinederr{#2}}
}

\def\mscunit{cm}%
\def\msckeywordstyle#1{\textbf{#1}}
\newcommand{\setmsckeyword}[1]{\mscset{/msc/msc keyword={#1}}}
\newcommand{\setmsckeywordstyle}[1]{\def\msckeywordstyle{#1}}%
\newcommand{\drawframe}[1]{\IfStrEq{#1}{yes}{\mscset{draw frame=}}{\IfStrEq{#1}{no}{\mscset{draw frame=none}}{}}}%
\newcommand{\drawinsthead}[1]{\IfStrEq{#1}{yes}{\mscset{draw head=}}{\IfStrEq{#1}{no}{\mscset{draw head=none}}{}}}
\newcommand{\drawinstfoot}[1]{\IfStrEq{#1}{yes}{\mscset{draw foot=}}{\IfStrEq{#1}{no}{\mscset{draw foot=none}}{}}}
\newcommand{\showgrid}{\mscset{draw grid}}
\newcommand{\nogrid}{\mscset{draw grid={none}}}
\newcommand{\setmscscale}[1]{\mscset{msc scale=#1}}%
\newcommand{\messarrowscale}[1]{\mscset{arrow scale=#1}}%

%\mscset but globally
\def\msc@global@set#1{\globaldefs=1\relax\mscset{#1}\globaldefs=0\relax}%

% the msc-environment
% \begin{msc}[options][headerpos]{mscname}
% ...definition of the MSC...
% \end{msc}
%\regionend{instname}
\def\msc{%
  \pgfutil@ifnextchar[\msc@mscopt{\msc@mscopt[l]}
}
\def\msc@mscopt[#1]{%
  % \msc@titlejustification says how the title should be justified
  % Justification is relative to the total width of the msc
  % l: left (default)
  % c: centered
  % r: right
  \ifx#1l
    \mscset{title position=left}
  \else \ifx#1c
      \mscset{title position=center}
    \else \ifx#1r
        \mscset{title position=right}
      \else
        \pgfutil@ifundefined{msc@tikzstarted}
        {
          \tikzpicture[/msc,#1]%
          \def\msc@tikzstarted{}}%
        {
          \relax}
      \fi
    \fi
  \fi
  \pgfutil@ifnextchar[{\msc@mscopt}{\msc@mscnoopt}
}
% core of msc with options parsed -
\def\msc@mscnoopt#1{% parse name
  % #1: mscname
  \pgfutil@ifundefined{msc@tikzstarted}
    {
      \tikzpicture\def\msc@tikzstarted{}%
    }%
    {\relax}
  % Options handling ends here
  \c@mscinstcnt 0\relax%  initialize number of instances to 0
  \c@condition 0\relax%  initialize number of condition to 0
  \c@msclevelcnt 1\relax% initialize level to 1
  \gdef\c@maxlevelcnt{0}% initialize maximum encountered level to 0
%   \msc@global@set{
%     }
  \mscset{
    /tikz/scale/.expanded=\mscget{msc scale},                                              
    /tikz/every node/.style/.expanded={scale/.expanded=\mscget{msc scale}},
    instance/envleft/no/.initial=0,
    instance/envright/no/.initial=1,
    instanceno/0/name/.initial=envleft,%
    instanceno/1/name/.initial=envright,
    instance/envleft/type/.initial=environment,
    instance/envright/type/.initial=environment,
    instance/envleft/region/.initial=normal,
    instance/envright/region/.initial=normal,
    instance/envleft/status/.initial=on,
    instance/envright/status/.initial=on,
    /msc/msc/name/.initial={#1}
  }
  \pgfmathparse{0-\mscget{head top distance} - \mscget{head height}}
  \xdef\msc@tempa{\pgfmathresult}
  \coordinate (msc@level0) at (0,\msc@tempa pt);
  \coordinate (msc@nodeenvright) at (0,\msc@tempa pt);
  \coordinate (msc@nodeenvleft) at  (0,\msc@tempa pt);
  \coordinate (msc@footenvleft) at (msc@nodeenvleft);
  \coordinate[below=\mscget{first level height} of msc@level0] (msc@level1);
}
\def\msc@drawgrid{
  \begin{pgfonlayer}{background}
    \pgfpointanchor{current bounding box}{south west}
    \pgfmathparse{ceil(\pgf@x/\pgf@xx)}%pgf@xx stores 1 of current unit (e.g. 1cm)
    \edef\msg@xa{\pgfmathresult}%
    \pgfmathparse{ceil(\pgf@y/\pgf@yy)}%
    \edef\msg@ya{\pgfmathresult}%
    \pgfpointanchor{current bounding box}{north east}
    \pgfmathparse{floor(\pgf@x/\pgf@xx)}%
    \edef\msg@xb{\pgfmathresult}%
    \pgfmathparse{floor(\pgf@y/\pgf@yy)}%
    \edef\msg@yb{\pgfmathresult}%
    \path (\msg@xa,\msg@ya) to[/msc/\mscget{draw grid}](\msg@xb,\msg@yb);
  \end{pgfonlayer}
}
%\def\endmsc[options]
\def\endmsc{%
%   \let\setlength\msc@OrigSL
  \pgfutil@ifnextchar[\msc@endmsc{\msc@endmsc[]}
  \endtikzpicture
  \global\let\msc@tikzstarted\relax
}
\def\msc@endmsc[#1]{
  \begin{pgfscope}
    \mscset{#1}
    \ifnum0&lt;\c@mscinstcnt\relax
      \ifnum\c@msclevelcnt&lt;\c@maxlevelcnt\relax
        \pgfmathparse{\c@maxlevelcnt-\the\c@msclevelcnt}
        \pgfkeys{/pgf/number format/precision=0}
        \pgfmathroundto{\pgfmathresult}
        \nextlevel[\pgfmathresult]%add missing levels
      \fi
      \mscset{level height=\mscget{last level height}}
      \nextlevel %add last but one level
      \foreach \msc@tempa in {1,...,\c@mscinstcnt} {%
        \stop[instance end=foot,#1]{\mscget{instanceno/\msc@tempa/name}}
      }
      \nextlevel %add last level just to draw outstanding foots
    \else
      \coordinate (msc@footenvleft) at (msc@nodeenvright);
      \coordinate[below=\mscget{first level height} of msc@level0] (msc@level1);
    \fi
    \msc@drawenvironment
    \IfStrEq{none}{\mscget{draw grid}}{}{%we draw help grid
      \msc@drawgrid
    }
  \end{pgfscope}
}
\def\msc@drawenvironment{
  \path[line width=\mscget{line width}]
     let \p1=(msc@node\mscget{instanceno/1/name}.north),
         \p2=(msc@foot\mscget{instanceno/\the\c@mscinstcnt/name}.south),
         \p3=(current bounding box.south east),
         \p4=(current bounding box.north west)  in
          ({\x2+max(\mscget{right environment distance},\x3-\x2)},
          {\y2+min(-\mscget{foot distance},\y3-\y2)}) coordinate(msc@env@se) [draw=\mscget{draw frame}] rectangle
          ({\x1+min(-\mscget{left environment distance},\x4-\x1)},
           {\y1+max(\mscget{head top distance},\y4-\y1)}) coordinate(msc@env@nw);
     \path let \p1=(msc@env@nw),
                \p2=(msc@env@se) in
           (\x1,\y1) +(\mscget{title distance},-\mscget{title top distance})
          node[rectangle, anchor=north west, inner sep=0, align=\mscget{title
          position}, text
          width=(\x2-\x1)-2*\mscget{title distance}]
          {\msckeywordstyle{\mscget{msc keyword}} \mscget{msc/name}};
    \foreach \msc@tempa in {0,...,\c@msclevelcnt} {%create nodes for environment
     \path let \p1=(msc@env@se),
               \p2=(msc@env@nw),
               \p3=(msc@level\msc@tempa) in
         (\x2,\y3) coordinate[name=msc@nodeenvleft@r\msc@tempa,
                              alias=msc@nodeenvleft@l\msc@tempa] --
         (\x1,\y3) coordinate[name=msc@nodeenvright@l\msc@tempa,
                             alias=msc@nodeenvright@r\msc@tempa];
    }
   \pgfkeysifdefined{/msc/levelenv/havedraw}{
%     \tikzset{/msc/levelenv/draw/.show code}
      \mscset{/msc/levelenv/draw}
      \msc@global@set{/msc/levelenv/draw/.code={}}
    }{}
}
% \setmscvalues assigns compatible values to all msc-parameters
% Currently, three sets of values are supported: large, normal
% and small.
\def\setmscvalues#1{%
  \IfEqCase{#1}{%
    {large}{\mscset{#1 values}}%
    {normal}{\mscset{#1 values}}%
    {small}{\mscset{#1 values}}%
  }[\msc@unknownmscvalueserr{#1}]
}
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%                           HMSC
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\def\msckeywordstyle#1{\textbf{#1}}
\newcommand{\sethmsckeyword}[1]{\mscset{/msc/hmsc keyword={#1}}}%
\newcommand{\sethmsckeywordstyle}[1]{\def\hmsckeywordstyle{#1}}%

% \begin{hmsc}[headerpos]{hmscname}(llx,lly)(urx,ury)
\def\hmsc{\def\msc@key{hmsc} \pgfutil@ifnextchar[\msc@hmscopt{\msc@hmscopt[]}}
\def\msc@hmscopt[#1]{%
  \msc@global@set{/msc/draw code/.code={}}
  \ifx#1l
    \mscset{title position=left}
  \else \ifx#1c
      \mscset{title position=center}
    \else \ifx#1r
        \mscset{title position=right}
      \else
        \pgfutil@ifundefined{msc@tikzstarted}{
          \tikzpicture[#1]%
          \def\msc@tikzstarted{}
        }{\relax}
      \fi
    \fi
  \fi
  \pgfutil@ifnextchar[{\msc@hmscopt}{\msc@hmscnoopt}
}

\def\msc@hmscnoopt#1{%
  % #1: mscname
  \pgfutil@ifundefined{msc@tikzstarted}{
    \tikzpicture\def\msc@tikzstarted{}%
  }{\relax}
  \mscset{
    /tikz/scale/.expanded=\mscget{msc scale},                                              
    /tikz/every node/.style/.expanded={scale/.expanded=\mscget{msc scale}},
    /msc/\msc@key/name/.initial={#1}}
  \pgfutil@ifnextchar({\msc@hmsc}{}
}

\def\msc@hmsc(#1,#2)(#3,#4){
 \path (#1,#4) coordinate(msc@\msc@key @nw)
       (#3,#2) coordinate(msc@\msc@key @se);
}
%\end{hmsc}[options]
\def\endhmsc{\def\msc@key{hmsc}\pgfutil@ifnextchar[\msc@endhmsc{\msc@endhmsc[]}
  \endtikzpicture
  \global\let\msc@tikzstarted\relax
}
\def\msc@endhmsc[#1]{
  \begin{pgfscope}
    \mscset{#1}
    \pgfutil@ifundefined{pgf@sh@ns@msc@\msc@key @nw}{%use bounding box
      \path (current bounding box.north west)
      ++(-\mscget{west \msc@key\space margin},
      \mscget{north \msc@key\space margin}+\mscget{title top distance}+\heightof{\mscget{msc@key/name}}+\depthof{\mscget{\msc@key/name}})
      coordinate(msc@\msc@key @nw) (current bounding box.south east)
      ++(\mscget{east \msc@key\space margin},-\mscget{south \msc@key\space margin})
      coordinate(msc@\msc@key @se);
    }{}
    \IfStrEq{\mscget{title position}}{left}{%
      \path (msc@\msc@key @nw) +(\mscget{title distance},-\mscget{title top distance})
           node[anchor=north west,inner sep=0]
           {\msckeywordstyle{\mscget{\msc@key\space keyword}} \mscget{\msc@key/name}};
    }{
      \IfStrEq{\mscget{title position}}{center}{%
        \path let \p1=(msc@\msc@key @nw),
                  \p2=(msc@\msc@key @se) in
            (\x1/2+\x2/2,\y1) +(0,-\mscget{title top distance})
            node[anchor=north,inner sep=0]
            {\msckeywordstyle{\mscget{\msc@key\space keyword}} \mscget{\msc@key/name}};
      }{
        \IfStrEq{\mscget{title position}}{right}{%
        \path let \p1=(msc@\msc@key @nw),
                  \p2=(msc@\msc@key @se) in
            (\x2,\y1) +(-\mscget{title distance},-\mscget{title top distance})
            node[anchor=north east,inner sep=0]
            {\msckeywordstyle{\mscget{\msc@key\space keyword}} \mscget{\msc@key/name}};
        }{}
      }
    }
    \path[draw=\mscget{draw frame},line width=\mscget{line width}] (msc@\msc@key @nw)|-(msc@\msc@key @se)|-(msc@\msc@key @nw);
    \IfStrEq{none}{\mscget{draw grid}}{}{%we draw help grid
      \msc@drawgrid
    }
  \end{pgfscope}
  \mscset{/msc/draw code}
  \msc@global@set{/msc/draw code/.code={}}
}
%\hmscstartsymbol{nickname}(x,y)
\def\hmscstartsymbol{
  \edef\msc@nodetype{start symbol}
  \pgfutil@ifnextchar[\msc@nodenotext{\msc@nodenotext[]}
}
\def\msc@nodenotext[#1]#2{
  \edef\msc@options{#1} \edef\msc@name{#2}\def\msc@text{}
  \pgfutil@ifnextchar({\msc@nodeAt}{
    \edef\msc@tempb{[/msc,\msc@nodetype,#1](\msc@name){};}
    \expandafter\node\msc@tempb
  }
}
\def\msc@nodetext[#1]#2#3{
  \edef\msc@options{#1} \edef\msc@name{#2}\def\msc@text{#3}
  \pgfutil@ifnextchar({\msc@nodeAt}{
    \def\msc@tempb{[/msc,\msc@nodetype,#1](#2){#3};}
    \expandafter\node\msc@tempb
  }
}

\def\msc@nodeAt(#1,#2){
  \edef\msc@tempb{[/msc,\msc@nodetype,\msc@options](\msc@name) at (#1,#2) {\unexpanded\expandafter{\msc@text}};}
   \expandafter\node\msc@tempb
}
%\hmscendsymbol{nickname}(x,y)
\def\hmscendsymbol{
  \edef\msc@nodetype{end symbol}
  \pgfutil@ifnextchar[\msc@nodenotext{\msc@nodenotext[]}
}
%\hmscreference{nickname}{text}(x,y)
\def\hmscreference{
  \edef\msc@nodetype{reference}
  \pgfutil@ifnextchar[\msc@nodetext{\msc@nodetext[]}
}
%\hmsc condition{nickname}{text}(x,y)
\def\hmsccondition{
  \edef\msc@nodetype{condition}
  \pgfutil@ifnextchar[\msc@nodetext{\msc@nodetext[]}
}
%\hmscconnection{nickname}(x,y)
\def\hmscconnection{
  \edef\msc@nodetype{connection}
  \pgfutil@ifnextchar[\msc@nodenotext{\msc@nodenotext[]}
}
%\arrow{from-nickname}[coord-list]{to-n
\def\arrow{\pgfutil@ifnextchar[\msc@arrowopt{\msc@arrowopt[]}}
\def\msc@arrowopt[#1]#2{
  \def\msc@options{#1}
  \edef\msc@node{#2}
  \edef\msc@tempa{}
  \pgfutil@ifnextchar[\msc@arrowgetpath{\msc@arrow}
}
\def\msc@arrowgetpath[#1]{
  \StrSubstitute{#1}{(}{--(}[\msc@tempa]
  \msc@arrow
}
\def\msc@arrow#1{
  \edef\msc@tempb{[/msc,/tikz/line width=\mscget{line width},arrow style,\msc@options] (\msc@node)\msc@tempa--(#1);}
  \expandafter\draw\msc@tempb
}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%                           MSC documents
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% \mscdockeyword is the keyword representation of msc
\def\mscdockeywordstyle#1{\textbf{#1}}
\newcommand{\setmscdockeyword}[1]{\mscset{/msc/mscdoc keyword/.initial=mscdoc}}
\newcommand{\setmscdockeywordstyle}[1]{\def\mscdockeywordstyle{#1}}%

%\begin{mscdoc}[headerpos]{mscdocname}(llx,lly)(urx,ury)
\def\mscdoc{\edef\msc@key{mscdoc} \pgfutil@ifnextchar[\msc@hmscopt{\msc@hmscopt[]}}
%\end{mscdoc}[options]
\def\endmscdoc{\edef\msc@key{mscdoc}
  \pgfutil@ifnextchar[\msc@endhmsc{\msc@endhmsc[]}
  \endtikzpicture
  \global\let\msc@tikzstarted\relax
}
%\hmscreference{nickname}{text}(x,y)
\def\reference{\pgfutil@ifnextchar[\msc@nodenoname{\msc@nodenoname[]}}
\def\msc@nodenoname[#1]#2{
  \edef\msc@options{#1} \def\msc@text{#2}
  \pgfutil@ifnextchar({\msc@nodenonameAt}{
    \edef\msc@tempb{[/msc,reference,#1](\msc@name){\unexpanded\expandafter{\msc@text}};}
    \expandafter\node\msc@tempb
  }
}
\def\msc@nodenonameAt(#1,#2){
  \edef\msc@tempb{[/msc,reference,every reference,\msc@options] at (#1,#2) {\unexpanded\expandafter{\msc@text}};}
   \expandafter\node\msc@tempb
}
\def\separator{\pgfutil@ifnextchar[\msc@separator{\msc@separator[]}}
\def\msc@separator[#1]#2{
  \begin{pgfscope}
  \mscset{#1}
  \xdef\msc@tempb{[/msc,/tikz/line width=\mscget{line width},mscdash]
    let \noexpand\p1=(msc@mscdoc@nw), \noexpand\p2=(msc@mscdoc@se) in
    (\noexpand\x1,#2)--(\noexpand\x2,#2);}
  \end{pgfscope}
  \mscset{/msc/draw code/.append code/.expand once={\expandafter\draw\msc@tempb}}
}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Error and help messages
% We use the standard LaTeX2e facilities to generate error and help
% messages (for more info, see file lterror.dtx of LaTeX2e distribution).
%
%
% nickname already defined
\gdef\msc@nicknamedefinederr#1{%
  \PackageError{msc}{% error message
    nickname #1 already defined}{% help text
    You tried to use the nickname '#1' for a new\MessageBreak
    msc object (instance, reference, inline expression, etc.),\MessageBreak
    but the nickname is already assigned to another msc object.\MessageBreak
    press &lt;enter&gt; to continue (the new msc object will be ignored).}%
}
%instance already started
\gdef\msc@instancestarted#1{%
  \PackageError{msc}{% error message
    instance #1 is already active}{% help text
    You tried to create instance '#1' but this instance is \MessageBreak
    already active. Maybe try to stop it using "stop" command .\MessageBreak
    press &lt;enter&gt; to continue.}%
}
% no such msc reference error
\gdef\msc@refundefinederr#1{%
  \PackageError{msc}{% error message
    undefined reference with nickname: #1}{% help text
    You used '#1' as an reference nickname, but\MessageBreak
    there is no reference with that nickname.}%
}
% no such msc reference error
\gdef\msc@inlundefinederr#1{%
  \PackageError{msc}{% error message
    undefined inline with nickname: #1}{% help text
    You used '#1' as an inline nickname, but\MessageBreak
    there is no inline with that nickname.}%
}
% no such msc instance error
\gdef\msc@instundefinederr#1{%
  \PackageError{msc}{% error message
    undefined msc instance: #1}{% help text
    You used '#1' as an msc instance nickname, but\MessageBreak
    there is no msc instance with that nickname.}%
}
% level height is not a positive integer
\gdef\msc@notpositiveintegerwarn#1#2{%
  \PackageWarning{msc}{% error message
    parameter #1.#2 is a float when integer was expected -
    recovering by advancing by #1+1 levels where last level is scaled by 0.#2}
}
\gdef\msc@notpositiveintegererr#1{%
  \PackageError{msc}{% error message
    Could not parse as number: #1}{% help text
    The nextlevel should be a positive integer but instead #1 was given.}%
}

% unknown region style error
\gdef\msc@unknownregionstyleerr#1{%
  \PackageError{msc}{% error message
    unknown region style: #1}{% help text
    Known msc region styles are "coregion", "suspension", and "activation".\MessageBreak
    You used '#1'.}%
}
% region not started error
\gdef\msc@regionnotstartederr#1{%
  \PackageError{msc}{% error message
    no region is started for the instance "#1"}{% help text
    You tried to end a region for the instance "#1", \MessageBreak
    but no region has been started.}%
}
% region already started error
\gdef\msc@regionstartederr#1#2{%
  \PackageError{msc}{% error message
    region #2 is already started}{% help text
    You tried to start new region for the instance "#1", \MessageBreak
    while the previous region is still active.}%
}
% unknown self message label position error
\gdef\msc@unknownmscvalueserr#1{%
  \PackageError{msc}{% error message
    unknown set of msc-values: #1}{% help text
    Known sets of msc-values are "normal" and "small".\MessageBreak
    You used '#1'.}%
}
%################################################################################
%
\gdef\msc@illegaltitleplacement#1{%
  \PackageError{msc}{%
    illegal title placement specifier: #1}{% help text
    Valid title placement specifiers are:\MessageBreak
      l (left)\MessageBreak
      c (center)\MessageBreak
      r (right)}
}
%reading /usr/share/texlive/texmf-dist/tex/latex/base/latex.ltx
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