latex-packages/tests/math/mathsymb/test.tex

\documentclass{article}

\usepackage{mkessler-mathsymb}

\begin{document}
\[
f \colon  A \to  B
\]

\[
    B \leftarrow A \noloc f
\] 

\contra

\Warning widerspruch!

\circled{1} test.
\end{document}