I'm trying to compile the simplest MWE with NiceArray
environment from nicematrix
package
\documentclass{article}
\usepackage{nicematrix}
\begin{document}
\[
\begin{NiceArray}{ccc}
1 & 2 & 3
\end{NiceArray}
\]
\end{document}
The PDF compiles, but I'm receiving an unexpected error
! Package nicematrix Error: There is a problem. Maybe your environment
(nicematrix) {NiceArray} is empty. Maybe you have used l, c
(nicematrix) and r instead of L, C and R in the preamble of
(nicematrix) your environment.
(nicematrix) If you go on, the result may be incorrect.
Full log: here
ccc
byCCC