☰

强制 LuaTeX 输出换行符

tag-icon • tag-icon luatex white-space directlua
强制 LuaTeX 输出换行符

当我希望使用指令输出文本文件时，我遇到了一个问题\directlua。在我希望换行符出现的地方，我遇到了 TeX 问题。我的解决方案是调用dofile函数来获取从外部 Lua 脚本调用的字符串myNLChar。此字符串可以写入输出文件，它将是一个真正的换行符。

文件wrnl2of.lua：

myNLChar = "\n"

文件wrnl2of.tex：

This Lua\TeX\ document does not typeset anything
interesting. It outputs a three-line text file
which contains newline characters.\par
\directlua0{
  local myOutFile   = "\jobname.txt"
  local myLuaScript = "\jobname.lua"
  dofile (myLuaScript)
  derDateiname = io.open (myOutFile, "w")
  derDateiname:write ("Alaska"     .. myNLChar)
  derDateiname:write ("California" .. myNLChar)
  derDateiname:write ("Nebraska"   .. myNLChar)
  derDateiname:close ()
}

虽然这个策略效果不错，但我怀疑这个问题还有几种更优雅的解决方案。我渴望听到一些建议。

答案1

我在这里只用\string一个简单的例子

This Lua\TeX\ document does not typeset anything
interesting. It outputs a three-line text file
which contains newline characters.\par
\directlua{
  local myOutFile   = "\jobname.txt"
  local myNLChar = "\string\n"
  derDateiname = io.open (myOutFile, "w")
  derDateiname:write ("Alaska"     .. myNLChar)
  derDateiname:write ("California" .. myNLChar)
  derDateiname:write ("Nebraska"   .. myNLChar)
  derDateiname:close ()
}
\bye

您还可以更改\catcode反斜杠：

This Lua\TeX\ document does not typeset anything
interesting. It outputs a three-line text file
which contains newline characters.\par
\begingroup
\long\def\firstofone#1{#1}
\catcode`\/=0 %
\catcode`/\=12 %
/firstofone{%
/endgroup
/directlua{
  local myOutFile   = "/jobname.txt"
  local myNLChar = "\n"
  derDateiname = io.open (myOutFile, "w")
  derDateiname:write ("Alaska"     .. myNLChar)
  derDateiname:write ("California" .. myNLChar)
  derDateiname:write ("Nebraska"   .. myNLChar)
  derDateiname:close ()
}%
}
\bye

对于任何长度的 Lua 代码，最好还是用dofile()或require()来代替。例如，

\begin{filecontents*}{\jobname.lua}
function derDateiname(myOutFile)
  local derDateiname = io.open(myOutFile, "w")
  derDateiname:write("Alaska"     .. "\n")
  derDateiname:write("California" .. "\n")
  derDateiname:write("Nebraska"   .. "\n")
  derDateiname:close()
end
\end{filecontents*}
\documentclass{article}
\begin{document}
This Lua\TeX\ document does not typeset anything
interesting. It outputs a three-line text file
which contains newline characters.\par
\directlua{
  require("\jobname.lua")
  derDateiname("\jobname")
}
\end{document}

相关内容