zr-tex8r/README

## README
amsthm パッケージの \newtheoremstyle / \theoremstyle / \newtheorem
と同じ方式で、スタイルを変更した「証明型環境」を新たに定義できるようにする
機能を提供する。

 - \newprooflikestyle でスタイルを定義. 引数の意味は最後(9盤目)の
   ものがないことを除いて \newtheoremstyle と同じ.
 - \prooflikestyle{<スタイル>}: 以降に定義する証明型環境のスタイルを指定.
 - \newprooflike{<環境名>}{<ラベル>}: 証明型環境を定義.
 - なお, 既存命令/環境の上書きは「proof」のみ可.

## bxproofstyle.sty
%
% bxproofstyle.sty
%
%% package declaration
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{bxproofstyle}

%% preparations
\RequirePackage{amsthm}

%%--------------------------------------

%% \bxpy@style
% Current proof-like style. (macro)
\def\bxpy@style{plain}

%%<*> \newprooflikestyle{<name>}{<space above>}{<space below>}
%      {<body font>}{<indent amount>}{<proof head font>}
%      {<punctuation after head>}{<space after head>}
\newcommand{\newprooflikestyle}[8]{%
  \toks@{#4}%
  \def\@tempa{#8}\ifx\space\@tempa
    \toks@\@xp{\the\toks@ \thm@headsep\fontdimen\tw@\font\relax}%
  \else
    \def\@tempb{\newline}%
    \def\bxpy@tempa{\par}%
    \ifx\@tempb\@tempa
      \toks@\@xp{\the\toks@ \thm@headsep\z@skip
        \def\thmheadnl{\newline}}%
    \else\ifx\bxpy@tempa\@tempa
      \toks@\@xp{\the\toks@ \thm@headsep\z@skip
        \def\thmheadnl{\par}}%
    \else
      \toks@\@xp{\the\toks@ \thm@headsep#8\relax}%
    \fi\fi
  \fi
  \begingroup
  \thm@space@setup
  \@defaultunits\dimen@#5\z@skip\relax\@nnil
  \@defaultunits\@tempskipa#2\thm@preskip\relax\@nnil
  \@defaultunits\@tempskipb#3\thm@postskip\relax\@nnil
  \xdef\@gtempa{\thm@preskip\the\@tempskipa
    \thm@postskip\the\@tempskipb
    \parindent\the\dimen@\relax}%
  \endgroup
  \@temptokena\@xp{\@gtempa
    \thm@headfont{#6}\thm@headpunct{#7}%
  }%
  \@xp\xdef\csname bxpy@s@#1\endcsname{\the\toks@ \the\@temptokena}%
}

%%<*> \prooflikestyle{<name>}
\newcommand{\prooflikestyle}[1]{%
  \@ifundefined{bxpy@s@#1}{%
    \PackageWarning{amsthm}{Unknown proofstyle `#1'}%
    \def\bxpy@style{plain}%
  }{%
    \edef\bxpy@style{#1}%
  }%
}

%% \bxpy@s@plain
% The 'plain' style uses the default values.
\def\bxpy@s@plain{}

%%<*> \newprooflike{<env name>}{<label>}
\newcommand{\newprooflike}{\bxpy@new@prooflike}
\def\bxpy@new@prooflike#1#2{%
  \@xp\bxpy@ifdefinable\csname #1\endcsname{%
    \global\@xp\let\csname end#1\endcsname\bxpy@endprooflike
    \@xp\xdef\csname#1\endcsname{\@nx\bxpy@prooflike
      {\@xp\@nx\csname bxpy@s@\bxpy@style\endcsname}{#2}}}%
}

%% \bxpy@ifdefinable\CS{<proc>}
% Same as \@ifdefinable except that "\proof" is treated as definable.
\def\bxpy@cs@proof{\proof}
\def\bxpy@ifdefinable#1{%
  \def\bxpy@tempa{#1}%
  \ifx\bxpy@tempa\bxpy@cs@proof
    \expandafter\@firstofone
  \else
    \expandafter\@ifdefinable\expandafter#1%
  \fi
}

%% \bxpy@prooflike
\def\bxpy@prooflike#1#2{%
  \pushQED{\qed}%
  \normalfont
  \let\thmheadnl\relax
  \thm@headfont{\itshape}%
  \thm@headpunct{.}% add period after heading
  \thm@headsep \labelsep
  \thm@preskip=6\p@\@plus6\p@\relax
  \thm@postskip=\thm@preskip
  #1% style overrides
  % Here vertical spacing is processed in normal way of trivlist
  \topsep \thm@preskip
  \def\bxpy@label{#2}%
  \bxpy@prooflike@a
}
\def\bxpy@prooflike@a{%
  \@ifnextchar[%]
  {\bxpy@prooflike@b}{\bxpy@prooflike@a[\bxpy@label]}%
}
\def\bxpy@prooflike@b[#1]{%
  \par \trivlist
  \advance\@topsepadd-\thm@preskip %
  \advance\@topsepadd\thm@postskip %
  \item[\hskip\labelsep \the\thm@headfont
   #1\@addpunct{\the\thm@headpunct}]%
  \hskip-\labelsep \hskip\thm@headsep
  \ifx\thmheadnl\relax\else
    \leavevmode\thmheadnl
  \fi
  \ignorespaces
}

%% \bxpy@endprooflike
\def\bxpy@endprooflike{%
  \popQED\endtrivlist\@endpefalse
}

%%--------------------------------------
\endinput

## test-bxproofstyle.tex
\documentclass[a4paper]{article}
\usepackage{bxproofstyle}
\newtheorem{theorem}{Theorem}
\newprooflikestyle{bastard}
{7.5pt}{9pt}{\sffamily}{8em}{\ahofont}{!}{\newline}
\newcommand*\ahofont{\usefont{OT1}{cmfr}{m}{it}}
\prooflikestyle{bastard}
\newprooflike{proofwww}{Proof}
\begin{document}

\begin{theorem}
God exists.
\end{theorem}
% A famous proof given by Euler.
\begin{proofwww}
Sir,
\[ \frac{a + b^n}{n} = x. \]

Repondez!
\end{proofwww}

\end{document}
	amsthm パッケージの \newtheoremstyle / \theoremstyle / \newtheorem
	と同じ方式で、スタイルを変更した「証明型環境」を新たに定義できるようにする
	機能を提供する。

	- \newprooflikestyle でスタイルを定義. 引数の意味は最後(9盤目)の
	ものがないことを除いて \newtheoremstyle と同じ.
	- \prooflikestyle{<スタイル>}: 以降に定義する証明型環境のスタイルを指定.
	- \newprooflike{<環境名>}{<ラベル>}: 証明型環境を定義.
	- なお, 既存命令/環境の上書きは「proof」のみ可.
	%
	% bxproofstyle.sty
	%
	%% package declaration
	\NeedsTeXFormat{LaTeX2e}
	\ProvidesPackage{bxproofstyle}

	%% preparations
	\RequirePackage{amsthm}

	%%--------------------------------------

	%% \bxpy@style
	% Current proof-like style. (macro)
	\def\bxpy@style{plain}

	%%<*> \newprooflikestyle{<name>}{<space above>}{<space below>}
	% {<body font>}{<indent amount>}{<proof head font>}
	% {<punctuation after head>}{<space after head>}
	\newcommand{\newprooflikestyle}[8]{%
	\toks@{#4}%
	\def\@tempa{#8}\ifx\space\@tempa
	\toks@\@xp{\the\toks@ \thm@headsep\fontdimen\tw@\font\relax}%
	\else
	\def\@tempb{\newline}%
	\def\bxpy@tempa{\par}%
	\ifx\@tempb\@tempa
	\toks@\@xp{\the\toks@ \thm@headsep\z@skip
	\def\thmheadnl{\newline}}%
	\else\ifx\bxpy@tempa\@tempa
	\toks@\@xp{\the\toks@ \thm@headsep\z@skip
	\def\thmheadnl{\par}}%
	\else
	\toks@\@xp{\the\toks@ \thm@headsep#8\relax}%
	\fi\fi
	\fi
	\begingroup
	\thm@space@setup
	\@defaultunits\dimen@#5\z@skip\relax\@nnil
	\@defaultunits\@tempskipa#2\thm@preskip\relax\@nnil
	\@defaultunits\@tempskipb#3\thm@postskip\relax\@nnil
	\xdef\@gtempa{\thm@preskip\the\@tempskipa
	\thm@postskip\the\@tempskipb
	\parindent\the\dimen@\relax}%
	\endgroup
	\@temptokena\@xp{\@gtempa
	\thm@headfont{#6}\thm@headpunct{#7}%
	}%
	\@xp\xdef\csname bxpy@s@#1\endcsname{\the\toks@ \the\@temptokena}%
	}

	%%<*> \prooflikestyle{<name>}
	\newcommand{\prooflikestyle}[1]{%
	\@ifundefined{bxpy@s@#1}{%
	\PackageWarning{amsthm}{Unknown proofstyle `#1'}%
	\def\bxpy@style{plain}%
	}{%
	\edef\bxpy@style{#1}%
	}%
	}

	%% \bxpy@s@plain
	% The 'plain' style uses the default values.
	\def\bxpy@s@plain{}

	%%<*> \newprooflike{<env name>}{<label>}
	\newcommand{\newprooflike}{\bxpy@new@prooflike}
	\def\bxpy@new@prooflike#1#2{%
	\@xp\bxpy@ifdefinable\csname #1\endcsname{%
	\global\@xp\let\csname end#1\endcsname\bxpy@endprooflike
	\@xp\xdef\csname#1\endcsname{\@nx\bxpy@prooflike
	{\@xp\@nx\csname bxpy@s@\bxpy@style\endcsname}{#2}}}%
	}

	%% \bxpy@ifdefinable\CS{<proc>}
	% Same as \@ifdefinable except that "\proof" is treated as definable.
	\def\bxpy@cs@proof{\proof}
	\def\bxpy@ifdefinable#1{%
	\def\bxpy@tempa{#1}%
	\ifx\bxpy@tempa\bxpy@cs@proof
	\expandafter\@firstofone
	\else
	\expandafter\@ifdefinable\expandafter#1%
	\fi
	}

	%% \bxpy@prooflike
	\def\bxpy@prooflike#1#2{%
	\pushQED{\qed}%
	\normalfont
	\let\thmheadnl\relax
	\thm@headfont{\itshape}%
	\thm@headpunct{.}% add period after heading
	\thm@headsep \labelsep
	\thm@preskip=6\p@\@plus6\p@\relax
	\thm@postskip=\thm@preskip
	#1% style overrides
	% Here vertical spacing is processed in normal way of trivlist
	\topsep \thm@preskip
	\def\bxpy@label{#2}%
	\bxpy@prooflike@a
	}
	\def\bxpy@prooflike@a{%
	\@ifnextchar[%]
	{\bxpy@prooflike@b}{\bxpy@prooflike@a[\bxpy@label]}%
	}
	\def\bxpy@prooflike@b[#1]{%
	\par \trivlist
	\advance\@topsepadd-\thm@preskip %
	\advance\@topsepadd\thm@postskip %
	\item[\hskip\labelsep \the\thm@headfont
	#1\@addpunct{\the\thm@headpunct}]%
	\hskip-\labelsep \hskip\thm@headsep
	\ifx\thmheadnl\relax\else
	\leavevmode\thmheadnl
	\fi
	\ignorespaces
	}

	%% \bxpy@endprooflike
	\def\bxpy@endprooflike{%
	\popQED\endtrivlist\@endpefalse
	}

	%%--------------------------------------
	\endinput
	\documentclass[a4paper]{article}
	\usepackage{bxproofstyle}
	\newtheorem{theorem}{Theorem}
	\newprooflikestyle{bastard}
	{7.5pt}{9pt}{\sffamily}{8em}{\ahofont}{!}{\newline}
	\newcommand*\ahofont{\usefont{OT1}{cmfr}{m}{it}}
	\prooflikestyle{bastard}
	\newprooflike{proofwww}{Proof}
	\begin{document}

	\begin{theorem}
	God exists.
	\end{theorem}
	% A famous proof given by Euler.
	\begin{proofwww}
	Sir,
	\[ \frac{a + b^n}{n} = x. \]

	Repondez!
	\end{proofwww}

	\end{document}