Verbatim prostredi a \par

[Ladislav Kasparek]

  Dobry den,
jak pracuje verbatim prostredi je pekne popsano v TBN. Pokud
budu chtit nacis soubor pomoci \input do verb. prostredi, napr:

\def\setverb{\def\do##1{\catcode`##1=12}\dospecials}
{\obeyspaces \gdef\activespaces{\obeyspaces\let =\ }}
\def\listing{\bgroup\setverb\activespaces
  \def\par##1{\endgraf \ifx##1\par\leavevmode\fi ##1}
  \obeylines\tt\input plain.tex\relax\egroup}
\listing\end

na konci souboru (plain.tex) tex hlasi:

Runaway argument?
! File ended while scanning use of ^^M.
<inserted text>
                \par
<to be read again>
                   \relax
\listing ...\obeylines \tt \input plain.tex\relax
                                                  \egroup
l.8 \listing
            \end
?

Proc???
Problem jsem 'obesel' takto:

\def\setverb{\def\do##1{\catcode`##1=12}\dospecials}
{\obeyspaces \gdef\activespaces{\obeyspaces\let =\ }}
\def\listing{\bgroup\setverb\activespaces
    \def\nextpar{\ifx\next\par\leavevmode\fi\next}
    \def\par{\endgraf\afterassignment\nextpar\let\next=}
  \obeylines\tt\input plain.tex\relax\egroup}
\listing\end

Predem dekuji za vysvetleni.
Ladislav Kasparek