\input{umtest-preamble} \usepackage{unicode-math} \setmathfont{Cambria Math} \ExplSyntaxOn \NewDocumentCommand \mathstylename { } { \mathtt { \prg_case_int:nnn { \luatexmathstyle } { { \displaystyle } { \token_to_str:N \displaystyle } { \luatexcrampeddisplaystyle } { \token_to_str:N \crampeddisplaystyle } { \textstyle } { \token_to_str:N \textstyle } { \luatexcrampedtextstyle } { \token_to_str:N \crampedtextstyle } { \scriptstyle } { \token_to_str:N \scriptstyle } { \luatexcrampedscriptstyle } { \token_to_str:N \crampedscriptstyle } { \scriptscriptstyle } { \token_to_str:N \scriptscriptstyle } { \luatexcrampedscriptscriptstyle } { \token_to_str:N \crampedscriptscriptstyle } } { outside math } } } \ExplSyntaxOff \begin{document} $\mathstylename \over \mathstylename$ $\luatexUstack{\mathstylename \over \mathstylename}$ $\frac{\mathstylename}{\mathstylename}$ \end{document}