%	myclass.sty	coded by YIN Dian
%	Implement easy inter-class token definition with inheritance
%	Hist:	070807	First usable version coded. \newclass, \{set,get,prepend,append}interclasstoks
%			The tricky part is prepending stuffs to a token register, see TeX by Topics.
%		070808	Added \setclassnum and \registerXeTeXclasstoks
%		070809	Removed unnecessary \global's.
%               070810  Only register non-empty tokens.
%		071019	Added \getclassnum
%		071210	Changed \@foreach to \@for.
\catcode`\@=11
\ifx\@myclass@defined\@undefined
\def\@myclass@defined{\relax}
\input usefulmacros.sty
\catcode`\@=11
\def\@class@list{}
\def\newclass{\@ifnextchar[{\@newclass@param}{\@newclass}}
\def\@newclass@param[#1]#2{%
  \if!#1!
    \errmessage{Base class name shouldn't be empty.}%
  \fi
  \if!#2!
    \errmessage{Class name shouldn't be empty.}%
  \fi
  \@ifundefined{@@classname@#1}{%
    \errmessage{Base class not defined yet.}%
  }{}%
  \@ifundefined{@@classname@#2}{% if
    \@namedef{@@classname@#2}{\relax}%
    \@namedef{@@baseclass@#2}{#1}%
    \@for\@@class:=\@class@list\do{% for
      \if!\@@class!
      \else
        \@newinterclasstoks{#2}{\@@class}%
        \@newinterclasstoks{\@@class}{#2}%
        %\setinterclasstoks{#2}{\@@class}{\getinterclasstoks{#1}{\@@class}}% 
        %\setinterclasstoks{\@@class}{#2}{\getinterclasstoks{\@@class}{#1}}% 
        \copyinterclasstoks{#2}{\@@class}{#1}{\@@class}% 
        \copyinterclasstoks{\@@class}{#2}{\@@class}{#1}% 
      \fi
    }% end for
    \@newinterclasstoks{#2}{#2}%
    \edef\@class@list{\@class@list,#2}%
  }{% else
    \errmessage{Class already defined.}%
  }% end if
}
\def\@newclass#1{%
  \if!#1!
    \errmessage{Class name shouldn't be empty.}%
  \fi
  \@ifundefined{@@classname@#1}{% if
    \@namedef{@@classname@#1}{\relax}%
    \@for\@@class:=\@class@list\do{% for
      \if!\@@class!
      \else
        \@newinterclasstoks{#1}{\@@class}%
        \@newinterclasstoks{\@@class}{#1}%
      \fi
    }% end for
    \@newinterclasstoks{#1}{#1}%
    \edef\@class@list{\@class@list,#1}%
  }{% else
    \errmessage{Class already defined.}%
  }% end if
}
\def\getbaseclass#1#2{%
  \@ifundefined{@@baseclass@#1}{\def#2{}}{\edef#2{\csname @@baseclass@#1\endcsname}}%
}
\def\@newinterclasstoks#1#2{%
  \expandafter\newtoks\csname @@interclasstoks@#1@#2\endcsname
  \csname @@interclasstoks@#1@#2\endcsname={}%\meaning #1, \meaning #2}%
  %%\expandafter\gdef\csname @@interclasstoks@#1@#2\endcsname{}%
}
\def\setinterclasstoks#1#2#3{%
  \csname @@interclasstoks@#1@#2\endcsname={#3}%
  %%\expandafter\edef\csname @@interclasstoks@#1@#2\endcsname{#3}%
}
\def\getinterclasstoks#1#2{%
  \expandafter\the\csname @@interclasstoks@#1@#2\endcsname
  %%\csname @@interclasstoks@#1@#2\endcsname
}
\def\copyinterclasstoks#1#2#3#4{% (#1, #2) <- (#3, #4)
  \expandafter\csname @@interclasstoks@#1@#2\endcsname\expandafter{\expandafter\the\csname @@interclasstoks@#3@#4\endcsname}%
}
\def\prependinterclasstoks#1#2#3{%
  \toks0={#3}%
  \edef\@@prepend@act{\csname @@interclasstoks@#1@#2\endcsname={\the\toks0
    \expandafter\the\csname @@interclasstoks@#1@#2\endcsname}}%
  \@@prepend@act
  %%\expandafter\edef\csname @@interclasstoks@#1@#2\endcsname{#3\csname @@interclasstoks@#1@#2\endcsname}%
}
\def\appendinterclasstoks#1#2#3{%
  \expandafter\csname @@interclasstoks@#1@#2\endcsname\expandafter{\the\csname @@interclasstoks@#1@#2\endcsname #3}%
  %%\global\expandafter\edef\csname @@interclasstoks@#1@#2\endcsname{\csname @@interclasstoks@#1@#2\endcsname #3}%
}
\def\showallinterclasstoks{%
  \par
  \begingroup
  \@for\class:=\@class@list\do{%
     \if!\class!
     \else
       \@for\anotherclass:=\@class@list\do{%
         \if!\anotherclass!
         \else
           [\class, \anotherclass]: %\csname @@interclasstoks@\class @\anotherclass\endcsname
           \expandafter\the\csname @@interclasstoks@\class @\anotherclass\endcsname
           \hfil\break
         \fi
       }%
     \fi
  }%
  \endgroup
}
\newlinechar`\^^J
\def\setclassnum#1#2{%
  \expandafter\chardef\csname @@classnum@#1\endcsname=#2\relax
}
\def\getclassnum#1{%
  \csname @@classnum@#1\endcsname
}
\def\mydbgmessag@#1{}
\def\registerXeTeXclasstoks{%
  \@for\class:=\@class@list\do{%
    \@ifundefined{@@classnum@\class}{}{%
      \@for\anotherclass:=\@class@list\do{%
        \@ifundefined{@@classnum@\anotherclass}{}{%
          \edef\@@temp@macro{\the\csname @@interclasstoks@\class @\anotherclass\endcsname}%
          \ifx\@@temp@macro\empty
          \else
            \edef\@@temp@macro{\@@temp@macro}%
            \ifx\@@temp@macro\empty
            \else
              \edef\@@register@act{\noexpand\XeTeXinterchartoks\csname @@classnum@\class\endcsname
                \csname @@classnum@\anotherclass\endcsname\noexpand{\expandafter\the\csname
                @@interclasstoks@\class @\anotherclass\endcsname\noexpand}}%
              \@@register@act
              \edef\@@register@act{\noexpand\mydbgmessag@\noexpand{Registered (\expandafter\number
                \csname @@classnum@\class\endcsname, \expandafter\number
                \csname @@classnum@\anotherclass\endcsname)\noexpand}}%
              \@@register@act
              \mydbgmessag@{Registered (\class, \anotherclass) token: \expandafter\the\csname
                @@interclasstoks@\class @\anotherclass\endcsname ^^J}%
            \fi
          \fi
        }%
      }%
    }%
  }%
}
\fi
