Strikeout all text, including enumerated lists

Question

Is it possible to define an environment that strikes out all text, even in enumerated lists?

I am basically trying automate what is currently being done manually in Microsoft Word. I have a body of text and I'm told which parts are new, which parts are unchanged, and which parts have been removed since the last update.

Newly added text has to appear in bold (which is straightforward enough), but anything that has been removed needs to appear struck out. The soul and ulem packages get me partly there, and although they can strike out entire paragraphs, they fail when given more than one paragraph at once. I also cannot do e.g. \sout{\begin{enumerate}\item asdf\end{enumerate}}, and if I just wrap each \item in with \sout, then the actual item number still appears unstruckout.

The type of text that I am trying to strike out is pretty much limited to ordinary paragraphic text and nested enumerated lists (i.e. no maths, no graphics, no figures, no headings, etc.) and will likely never be longer around half a page for each new/deleted region.

I'm not looking for anything precise or pretty, e.g. if the strikeout spans the entire width of the page just to strike out one word, that is fine. I'm also open to suggestions about alternative ways to typeset deleted text.

What I have so far is borrowed from @Werner's answer here, and I can place a horizontal rule through each line of a paragraph, but it borks enumerated lists.

\documentclass[a4paper]{article}

\usepackage{lipsum}

\newbox\strikeoutlinebox

% sorry for the messy boxes ... is there a cleaner way?
\def\strikeoutline{%
  \vbox to 0pt{%
    \vskip -4pt%
    \hbox to 0pt{%
      \vbox{\hsize\wd\strikeoutlinebox\hrule width \hsize}%
      \hskip 0pt minus 1fil%
    }%
    \vskip 0pt plus 1fil%
  }%
  \box\strikeoutlinebox
}

\def\fullstrikeout{%
  \setbox\strikeoutlinebox\lastbox
  \ifvoid\strikeoutlinebox
    \noindent\ignorespaces
  \else
    \unskip\unpenalty
    \begingroup\fullstrikeout\space\endgroup
    \strikeoutline
  \fi
}

% is this bad? it's probably bad ...
\newenvironment{strikethrough}{%
  \begingroup
    \let\oldpar=\par
    \def\par{\oldpar\fullstrikeout}%
    \vbox\bgroup
}{%
    \par\egroup
    \let\par=\oldpar
  \endgroup
}

\begin{document}

\begin{strikethrough}
\lipsum[0-3]
\end{strikethrough}

\end{document}

The above is a WIP but as you can probably tell I really have little clue what I'm doing.

Answer 1

FWIW, in ConTeXt, the \overstike macro works well with enumerated lists. Here is an example:

\starttext

\overstrike{
\startitemize[n]
  \item \input ward
    \startitemize[i]
      \item \input zapf
    \stopitemize
  \item \input tufte
\stopitemize}


\stoptext

which gives

Answer 2

Maybe you can use something based on Tikz.

Option 1:

The following is based on Gonzalo Medina's answer:

\documentclass{article}
\usepackage{tikzpagenodes}
\usetikzlibrary{patterns}
\usetikzlibrary{calc}

\makeatletter
\tikzset{%
  remember picture with id/.style={%
    remember picture,
    overlay,
    save picture id=#1,
  },
  save picture id/.code={%
    \edef\pgf@temp{#1}%
    \immediate\write\pgfutil@auxout{%
      \noexpand\savepointas{\pgf@temp}{\pgfpictureid}}%
  },
  if picture id/.code args={#1#2#3}{%
    \@ifundefined{save@pt@#1}{%
      \pgfkeysalso{#3}%
    }{
      \pgfkeysalso{#2}%
    }
  }
}

\def\savepointas#1#2{%
  \expandafter\gdef\csname save@pt@#1\endcsname{#2}%
}

\def\tmk@labeldef#1,#2\@nil{%
  \def\tmk@label{#1}%
  \def\tmk@def{#2}%
}

\tikzdeclarecoordinatesystem{pic}{%
  \pgfutil@in@,{#1}%
  \ifpgfutil@in@%
    \tmk@labeldef#1\@nil
  \else
    \tmk@labeldef#1,(0pt,0pt)\@nil
  \fi
  \@ifundefined{save@pt@\tmk@label}{%
    \tikz@scan@one@point\pgfutil@firstofone\tmk@def
  }{%
  \pgfsys@getposition{\csname save@pt@\tmk@label\endcsname}\save@orig@pic%
  \pgfsys@getposition{\pgfpictureid}\save@this@pic%
  \pgf@process{\pgfpointorigin\save@this@pic}%
  \pgf@xa=\pgf@x
  \pgf@ya=\pgf@y
  \pgf@process{\pgfpointorigin\save@orig@pic}%
  \advance\pgf@x by -\pgf@xa
  \advance\pgf@y by -\pgf@ya
  }%
}
\newcommand\tikzmark[2][]{%
\tikz[remember picture with id=#2] #1;}
\makeatother

\newcommand\BoxedText[3][]{%
\begin{tikzpicture}[remember picture,overlay]
\draw[#1]
  let \p1=(pic cs:#2), \p2=(pic cs:#3) in
  ([yshift=-0.8ex]\p1) --
  ([yshift=2ex]\p1) --
  ([xshift=3pt,yshift=2ex]\p1-|current page text area.east) --
  ([xshift=3pt,yshift=2ex]\p2-|current page text area.east) --
  ([yshift=2ex]\p2) --
  ([yshift=-0.8ex]\p2) --
  ([xshift=-3pt,yshift=-0.8ex]\p2-|current page text area.west) --
  ([xshift=-3pt,yshift=-0.8ex]\p1-|current page text area.west) --
  cycle
;
\end{tikzpicture}%
}



\usepackage{lipsum}

\begin{document}

\BoxedText[pattern=horizontal lines]{start1}{end1}
\BoxedText[draw=gray!70!black,fill=gray!50,ultra thick]{start2}{end2}

Some text goes here.\tikzmark{start1} \lipsum[1]
\begin{enumerate}
\item An item
\item Another item
\item Final item
\end{enumerate}
\lipsum[2]
\section{A section head}
A line of text.
\tikzmark{end1}
After the strikeout. Some text goes here. Some text goes here. Some
text goes here. Some text goes here.Some text goes
here.\tikzmark{start2} Some text goes here. Some text goes here. Some
text goes here. Some text goes here. Some text Some text goes
here.\tikzmark{end2}

\end{document}

The down side is that each section that has to be marked must have its own start and end \tikzmark defined. Note, LaTeX has to be run three times to make a correct PDF.

Option 2:

If the text is always in full paragraphs (not starting or ending mid-sentence like option 1), you could use the mdframed package, which leads to simpler code:

\documentclass{article}

\usepackage{lipsum}
\usepackage[framemethod=tikz]{mdframed}
\usetikzlibrary{patterns}

\mdfdefinestyle{strikeoutbox}{%
  linecolor=black,%
  apptotikzsetting={\tikzset{mdfbackground/.append style={%
        draw=gray!10,pattern=horizontal lines}
                                %color=blue!20}
      }},%
  innertopmargin=\topskip,
}

\begin{document}

Some text goes here.
\begin{mdframed}[style=strikeoutbox]
\lipsum[1]
\begin{enumerate}
\item An item
\item Another item
\item Final item
\end{enumerate}
\lipsum[2]

\section{A section head}
A line of text.
\end{mdframed}
After the strikeout. Some text goes here. Some text goes here. Some
text goes here. Some text goes here.Some text goes
here. Some text goes here. Some text goes here. Some
text goes here. Some text goes here. Some text Some text goes
here.

\end{document}

Final remark

For both options you can use Philippe Goutet's answer on customizing an existing pattern in order to get the stripes further apart, in a different colour, etc.