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%
% Copyright (C) 2010-2014 by Ulrich M. Schwarz
% Copyright (C) 2019      by Frank Mittelbach
% Copyright (C) 2020-     by Yukai Chou
%
% This file may be distributed and/or modified under the conditions of
% the LaTeX Project Public License, version 1.3c.
% The license can be obtained from
% http://www.latex-project.org/lppl/lppl-1-3c.txt
%
%\fi
%
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%<*thmbox>
%\fi
% The \pkg{thmbox} package does something else: instead of having a separate
% environment, we have to use a command different from
% |\newtheorem| to get the boxed style. Fortunately,
% \thmtools stores the command as |\thmt@theoremdefiner|, so we
% can modify it. (One of the perks if extension writer and framework writer
% are the same person.) So, in contrast to the previous example, this time
% we need to do something before the actual |\newtheorem| is
% called.
%    \begin{macrocode}
\define@key{thmdef}{thmbox}[L]{%
  \thmt@trytwice{%
    \let\oldproof=\proof
    % backup \\proof, gh32
    \expandafter\let\csname old\@backslashchar proof\expandafter\endcsname
                    \csname    \@backslashchar proof\endcsname
    \let\oldendproof=\endproof
    \let\oldexample=\example
    \let\oldendexample=\endexample
    \RequirePackage[nothm]{thmbox}
    \let\proof=\oldproof
    % restore thmbox's change to \\proof, gh32
    \expandafter\let\csname    \@backslashchar proof\expandafter\endcsname
                    \csname old\@backslashchar proof\endcsname
    \let\endproof=\oldendproof
    \let\example=\oldexample
    \let\endexample=\oldendexample
    \def\thmt@theoremdefiner{\newboxtheorem[#1]}%
  }{}%
}%
%    \end{macrocode}
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%</thmbox>
%\fi