I'm using MiKTeX (Console) 2.9.6673 on a Windows 10 Pro. Consider the following minimal-not-working-example.
\documentclass{article}
\usepackage{mhchem}
\begin{document}
\ce{H2O}
\end{document}
The document body contains nothing else but \ce{}
, and it doesn't compile, throwing tons of errors. I don't understand the problem. I have every required package (mhchem, chemgreek, l3kernel, l3packages). Some errors:
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!
! LaTeX error: "kernel/command-not-defined"
!
! Control sequence \regex_match:NnTF undefined.
!
! See the LaTeX3 documentation for further information.
!
! For immediate help type H <return>.
!...............................................
l.53 ...nerate_variant:Nn \regex_match:NnTF { NV }
|'''''''''''''''''''''''''''''''''''''''''''''''
| This is a coding error.
|
| LaTeX has been asked to use a control sequence '\regex_match:NnTF':
| this has not been defined yet.
|...............................................
Here's the complete log (first error on line 375). They all seem to contain something regex-related. What can I do to solve this?
Best Answer
It seems placing
\usepackage{l3regex}
before\usepackage{mhchem}
solves the problem. I'm not sure whyl3regex
is not included by default bymhchem
if it makes use of the former, I didn't have a problem with this before reinstalling MiKTeX.