我的编辑器给了我一个前言文件以供使用。在我之前的笔记本电脑（刚刚被盗）上，我能够编译该文件。
但在我的新版本上，出现以下错误：
Runaway argument?
{\dim_set:Nn ##1{\fontdimen ##2##3}\dim_compare:nNnT ##1={0pt}{\settoheight \ET
C.
! Forbidden control sequence found while scanning use of \__cs_generate_from_si
gnature:nnNNNn.
<inserted text>
\par
l.1504 \int_case:nnn
#2
I suspect you have forgotten a `}', causing me
to read past where you wanted me to stop.
I'll try to recover; but if the error is serious,
you'd better type `E' or `X' now and fix your file.
! Undefined control sequence.
<argument> \LaTeX3 error:
The deprecated command '\int_case:nnn' has been o...
l.1504 \int_case:nnn
#2
The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!
! LaTeX error: "kernel/deprecated-command"
!
! The deprecated command '\int_case:nnn' has been or will be removed on
! 2015-07-14. Use instead '\int_case:nnF '.
!
! See the LaTeX3 documentation for further information.
!
! Type <return> to continue.
!...............................................
l.1504 \int_case:nnn
#2
|'''''''''''''''''''''''''''''''''''''''''''''''
| LaTeX does not know anything more about this error, sorry.
|
| Try typing <return> to proceed.
| If that doesn't work, type X <return> to quit.
|...............................................
! You can't use `macro parameter character #' in vertical mode.
l.1504 \int_case:nnn #
2
Sorry, but I'm not programmed to handle this case;
I'll just pretend that you didn't ask for it.
If you're in the wrong mode, you might be able to
return to the right one by typing `I}' or `I$' or `I\par'.
我在这个网站上找到了一些相关主题。并使用：
\usepackage{expl3}
\ExplSyntaxOn
\cs_new_eq:NN \str_case:nnn \str_case:nnF
\cs_new_eq:NN \str_case_x:nnn \str_case_x:nnF
\cs_new_eq:NN \int_case:nnn \int_case:nnF
\cs_set_eq:NN\tl_case:Nnn\tl_case:NnF
\ExplSyntaxOff
对我来说没用。非常感谢您的回答！