moveproofs.sty

% moveproofs: a package for auto-moving proofs to the appendix of a document.
% 
% (c) Daniel Haas, 2016
%
%% This program can be redistributed and/or modified under the terms
%% of the LaTeX Project Public License Distributed from CTAN archives
%% in directory macros/latex/base/lppl.txt.
% 
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{moveproofs}[2016/02/22 LaTex package for auto-moving proofs to the appendix]

\RequirePackage{pgfkeys}
\RequirePackage{pgfopts}
\RequirePackage{xparse}

% Namespace our key-value store.
\pgfkeys{/moveproofs/.is family}

% Set up the 'location' option, which may be set to 'inline' (don't move proofs) or 'appendix' (move proofs to the appendix).
\newif\ifmoveproofstoappendix
\pgfkeys{moveproofs,
  options/location/.is choice,
  options/location/inline/.code={\moveproofstoappendixfalse},
  options/location/appendix/.code={\moveproofstoappendixtrue},
}

% Set up the 'manual' option, which may be set to 'true' (the user must use \appendixproofsection and \appendixproof in
% order for proofs to appear in the appendix) or 'false' (default, proofs are automatically displayed in the appendix in a 
% section called 'Proofs'.
\newif\ifmanualappendix
\pgfkeys{moveproofs, options/manual/.is if=manualappendix}

% Set up the 'appendixsectionname' option, which takes a string, and (if 'manual=false'), will be used instead of 'Proofs'
% as the name of the appendix section where proofs are displayed.
\newcommand{\MPAppendixSectionName}{Proofs}
\pgfkeys{moveproofs, 
    options/appendixsectionname/.code={\renewcommand{\MPAppendixSectionName}{#1}}
}

% Set up the 'prependtoappendix' option, which may be set to 'true' (proofs are added to the beginning of the appendix)
% or 'false' (default, proofs are added to the end of the appendix). Option is only used if location=appendix, manual=false,
% and the user has already created their own appendix section.
\newif\ifprependtoappendix
\pgfkeys{moveproofs, options/prependtoappendix/.is if=prependtoappendix}

% Process the passed package options
\ProcessPgfOptions{moveproofs/options}

% Define a simple proof environment if it doesn't exist.
\newcommand{\BlackBox}{\rule{1.5ex}{1.5ex}}
\newcommand*{\MPQED}{\hfill\BlackBox\\[0.1mm]}
\makeatletter
\def\provideenvironment{\@star@or@long\provide@environment}
\def\provide@environment#1{%
        \@ifundefined{#1}%
                {\def\reserved@a{\newenvironment{#1}}}%
                {\def\reserved@a{\renewenvironment{dummy@environ}}}%
        \reserved@a
}
\def\dummy@environ{}
\makeatother
\provideenvironment{proof}{ \par\noindent{\bfseries\upshape Proof\ }}{\MPQED}

% Low-level commands for manipulating the kv-store.
\newcommand{\MPProofToStore}{}
\DeclareDocumentCommand{\MPStoreProof}{s m +m m}{
    % Pass the * argument through to \appendixproof
    \IfBooleanTF{#1}{
        \renewcommand{\MPProofToStore}[1]{\appendixproof*{##1}}
    }{
        \renewcommand{\MPProofToStore}[1]{\appendixproof{##1}}
    }
    \pgfkeys{moveproofs, 
            proofs/#2/content/.code={#3},
            proofs/#2/title/.code={#4},
            proofs/list/.append={\MPProofToStore{#2}}
    }
}
\newcommand{\MPGetProof}[1]{\pgfkeys{moveproofs, proofs/#1/content}}
\newcommand{\MPGetTitle}[1]{\pgfkeys{moveproofs, proofs/#1/title}}

% The \makeproof command lets you define a proof in the document.
% Arguments are a label for the proof, and the proof body itself.
% If called with a star (e.g., \makeproof*{theorem_label}{theorem body}), 
% the proof content will not be auto-wrapped in a proof environment, and you
% must manually insert your own with \begin{proof} and \end{proof}.
% Example usage: \makeproof{theorem_one}{$a = b$, so we're done.}.
\DeclareDocumentCommand{\makeproof}{s m +m m}{
    \IfBooleanTF{#1}{
        \MPStoreProof*{#2}{#3}{#4}%
    }{
        \MPStoreProof{#2}{#3}{#4}%
    }

    % Insert the proof directly into the document inline if required by package options.
    \ifmoveproofstoappendix
    \else
        \IfBooleanTF{#1}{
            \MPGetProof{#2}%
        }{
            \MPGetProof{#2}%
        }
    \fi
}

% The \appendixproof command lets you mark where a proof will be moved to.
% If location="appendix" was passed, it will create a subsection in the appendix with the proof in it.
% The argument is the theorem label you passed to \makeproof.
% If called with a star (e.g., \appendixproof*{theorem_label}), 
% the behavior will match that of \makeproof*.
% Example usage: \appendixproof{theorem_one}
\DeclareDocumentCommand{\appendixproof}{s m}{
\ifmoveproofstoappendix
    \subsection{\protect\MPGetTitle{#2}}\label{#2_proof}
    \IfBooleanTF{#1}{
        \MPGetProof{#2}%
    }{
        \MPGetProof{#2}%
    }
\else
\fi
}

% The \appendixproofsection command lets you add a section to contain proofs in the appendix.
% The section will only appear if location="appendix".
\newcommand{\appendixproofsection}[1]{\ifmoveproofstoappendix\section{#1}\fi}

% The \appendixproofnotice command lets you define a notice that the proofs have been moved to the appendix
% The section will only appear if location="appendix". The optional argument is a replacement for the default language.
\newcommand{\appendixproofnotice}[1][All proofs will appear in the appendix.]{\ifmoveproofstoappendix#1\fi}

% Internal use only: track existence of appendix and auto-add proofs to the appendix.
\let\oldappendix\appendix% Store \appendix
\newif\ifnoappendix % True if the user hasn't created an appendix
\newif\ifproofsinserted % True if this package has auto-inserted proofs into the document.
\noappendixtrue
\newcommand{\appendixprelim}{\clearpage\onecolumn}
\newcommand{\MPAppendixProofs}{
    \ifproofsinserted
    \else
        \ifmanualappendix
        \else
            \ifnoappendix
                \oldappendix
            \fi
            \appendixprelim
            \appendixproofsection{\MPAppendixSectionName}
            \pgfkeys{moveproofs, proofs/list}
            \proofsinsertedtrue
        \fi
    \fi
}

% Redefine the \appendix command to track whether the appendix exists and prepend content if necessary.
\renewcommand{\appendix}{% Update \appendix
    \oldappendix% Default \appendix
    \noappendixfalse% Mark appendix as created
    
    % Insert proofs at the beginning of the appendix if so specified.
    \ifprependtoappendix
        \MPAppendixProofs
    \fi
}

% Add all proofs to the end of the appendix if they weren't already prepended.
\AtEndDocument{\MPAppendixProofs}