\obeylines我对将 when放在一\begingroup...\endgroup对中这一事实感到困惑在环境中，该环境中的宏参数似乎仍然受到命令的影响\obeylines——我很可能忘记了一些令人尴尬的基本内容。
\documentclass{article}
\newtoks\tabtox
\newtoks\msctox
\begingroup
\lccode`~=`\^^M
\lowercase{%
\endgroup
\def\tst#1 #2 #3~{%
\global\tabtox=\expandafter{\the\tabtox
\textbf{#3,} #1\ #2
\par
}~% we want a `\par`
}%
}%
\NewDocumentEnvironment{startit}{}{%
\begingroup
\obeylines
\offinterlineskip
\everypar={\tst}
}{%
\the\msctox\par
\the\tabtox
}
\NewDocumentCommand{\finishthis}{+m}{%
\endgroup
\msctox={#1}
}
%% |=====8><-----| %%
\parindent0pt
\begin{document}
\thispagestyle{empty}
The argument to \string\finishthis\ seems still to\\be under the influence of \string\obeylines:
\begin{startit}
1 a b
2 c d
3 e f
4 g h
\finishthis{a
b
c
f}
\end{startit}
\bigskip
This works as expected:
\tabtox={}%
\begingroup
\obeylines
\offinterlineskip
\everypar={\tst}
1 a b
2 c d
3 e f
4 g h
\endgroup
\msctox={a
b
c
f}
\the\msctox\par
\the\tabtox
\end{document}
答案1
您想在组结束后抓取参数，以便它获得正常的 catcode 5 行结束：
\documentclass{article}
\newtoks\tabtox
\newtoks\msctox
\begingroup
\lccode`~=`\^^M
\lowercase{%
\endgroup
\def\tst#1 #2 #3~{%
\global\tabtox=\expandafter{\the\tabtox
\textbf{#3,} #1\ #2%%%%%%%%%%
\par
}~% we want a `\par`
}%
}%
\NewDocumentEnvironment{startit}{}{%
\begingroup
\obeylines
\offinterlineskip
\everypar={\tst}%%%%%%%%%%
}{%
\the\msctox\par
\the\tabtox
}
\NewDocumentCommand{\finishthis}{}{%
\endgroup
\finishthisinternal
}
\def\finishthisinternal#1{%
\msctox={#1}%%%%%%%%%%
}
%% |=====8><-----| %%
\parindent0pt
\begin{document}
\thispagestyle{empty}
This works as expected:
\begin{startit}
1 a b
2 c d
3 e f
4 g h
\finishthis{a
b
c
f}
\end{startit}
\bigskip
This works as expected:
\tabtox={}%
\begingroup
\obeylines
\offinterlineskip
\everypar={\tst}
1 a b
2 c d
3 e f
4 g h
\endgroup
\msctox={a
b
c
f}
\the\msctox\par
\the\tabtox
\end{document}