如何列印環境中計數器的開始值和結束值？

Question

我正在開發用於標準化測試的格式化系統。在測試的每個部分中，我可能會選擇將一組連續的問題納入環境中。

\begin{passagequestions}
    \begin{question} % question 1, or whichever this is.
    \end{question}
    % and so on
\end{passagequestions}

無論何時使用，櫃檯questioncount都設在外面。passagequestions假設這question只是增加問題編號，即通過\stepcounter{questioncount}。

在 的每個實例的開頭passagequestions，我想命名屬於問題組的所有問題。的每個實例passagequestions都應以 開頭Questions {0}--{1} are based on the following passage.，其中{0}是第一個問題的索引（可能是也可能不是 1），{1}是最後一個問題的索引。

我之前的解決方案是先使用 atotcount來追蹤問題組的長度，但我的印像是這不是一個好主意。

Answer 1

編輯更好的版本見最後。

與維爾納類似，但我使用的是假標籤，一旦hyperref使用就會破裂。

\documentclass{article}

\usepackage{refcount}

\newcounter{passage}%
\newcounter{question}

\newenvironment{question}{\refstepcounter{question}}{}



\makeatletter
\newenvironment{passagequestions}{%
  \refstepcounter{passage}%
  % Store the fake label for the beginning
  \immediate\write\@auxout{%
    \string\newlabel{passagestart::\number\value{passage}}{{\number\value{question}}{\thepage}}%
  }%
  Questions \getrefnumber{passagestart::\number\value{passage}} -- \getrefnumber{passageend::\number\value{passage}} are based on the following passage.
}{%Store the fake label for the end
  \immediate\write\@auxout{%
    \string\newlabel{passageend::\number\value{passage}}{{\number\value{question}}{\thepage}}%
  }%
}
\makeatother





\begin{document}

\begin{passagequestions}
\begin{question}
\end{question}

\begin{question}
\end{question}
\begin{question}
\end{question}
\begin{question}
\end{question}


\end{passagequestions}

\begin{passagequestions}

\begin{question}
\end{question}

\begin{question}
\end{question}
\begin{question}
\end{question}
\begin{question}
\end{question}


\end{passagequestions}


\end{document}

編輯更好的版本

\documentclass{article}

\usepackage{xpatch}
\usepackage{refcount}
\usepackage{xcolor}
\newif\ifnewpassage
\newpassagefalse

\newcounter{passage}%
\newcounter{question}


%Define some dummy question environment

\newenvironment{question}{%
\vskip0.3\abovedisplayskip

\refstepcounter{question}%
\colorbox{yellow}{\bfseries \textcolor{blue}{Question \thequestion}}%

\addvspace{0.5\baselineskip}
}{\vskip0.5\belowdisplayskip}

% Add some code to the question environment
\makeatletter

\newcommand{\storefakelabel}[3][\number\value{passage}]{%
  \immediate\write\@auxout{%
    \string\newlabel{#2#1}{{#3}{\thepage}}%
  }%
}

\newcommand{\passagestartprefix}{passagestart:}
\newcommand{\passageendprefix}{passageend:}

\newcommand{\getstartquestion}{%
  \getrefnumber{\passagestartprefix\number\value{passage}}
}

\newcommand{\getendquestion}{%
  \getrefnumber{\passageendprefix\number\value{passage}}%
}

\xapptocmd{\question}{% Append the stuff after(!!!) the question startup code has been done!
  \ifnewpassage%
  \storefakelabel{\passagestartprefix}{\number\value{question}}%
  \global\newpassagefalse%
  \fi%
}{}{}

\newcommand{\passagequestionsheading}{%
\colorbox{green}{Questions \getstartquestion -- \getendquestion\ are based on the following passage.}
}

\newenvironment{passagequestions}{%
  \vskip\abovedisplayskip%
  \newpassagetrue% Started a new passage
  \refstepcounter{passage}%
  \colorbox{red}{\large \bfseries Questions passage \thepassage}%

  \passagequestionsheading

}{%
  % Store the fake label for the end
  \storefakelabel{\passageendprefix}{\number\value{question}}%
  \vskip\belowdisplayskip%
}
\makeatother



\begin{document}

\begin{passagequestions}
\begin{question}
  Why does \LaTeXe\ provide that much fun?
\end{question}

\begin{question}
\end{question}
\begin{question}
\end{question}
\begin{question}
\end{question}


\end{passagequestions}

\begin{passagequestions}

\begin{question}
\end{question}

\begin{question}
\end{question}
\begin{question}
\end{question}
\begin{question}
\end{question}


\end{passagequestions}


\end{document}

Answer 2

這是您問題的非正式解決方案：

1. passagequestions用 a標記環境的開始和結束\label

2. 回想一下環境開始時的這些\labels 。\refpassagequestions

您必須確保計數器步進能夠在其呼叫的環境中倖存\@currentlabel下來。\label\ref

\documentclass{article}

\newcounter{question}
\newcounter{passagequestions}
\newenvironment{passagequestions}
  {\stepcounter{passagequestions}%
   \par\addvspace{\bigskipamount}\noindent
   Questions \ref{pq-\thepassagequestions-start}--\ref{pq-\thepassagequestions-end} are based on the following passage\ldots
   \par
   \renewcommand{\question}{%
     \oldquestion%
     \label{pq-\thepassagequestions-start}%
     \global\let\question\oldquestion}}%
  {\label{pq-\thepassagequestions-end}}

\makeatletter
\newenvironment{question}
  {\stepcounter{question}%
   \xdef\@currentlabel{\thequestion}%
   \par\addvspace{\baselineskip}%
   \textbf{Question~\thequestion}:}
  {}
\makeatother

\let\oldquestion\question

\begin{document}

\begin{passagequestions}
  This is the first passage\ldots
  \begin{question}
    First question
  \end{question}
  \begin{question}
    Second question
  \end{question}
  \begin{question}
    Third question
  \end{question}
\end{passagequestions}

\begin{passagequestions}
  This is the second passage \ldots
  \begin{question}
    First question
  \end{question}
  \begin{question}
    Second question
  \end{question}
  \begin{question}
    Third question
  \end{question}
\end{passagequestions}

\end{document}