+\newcommand{\setmerge}{\mergeof{}{}{}}
+\newcommand{\setmergeof}[3]{\mergeof{#1}{#2}{#3}}
+\newcommand{\stmtmergeof}[3]{\mergeof{#1}{#2}{#3}}
+
+%\newcommand{\setmergeof}[3]{\setmerge\left\lgroup #1 \;\middle\lmoustache\; #2 \;\middle\rmoustache\; #3 \right\rgroup}
+%\newcommand{\setmergeof}[3]{\setmerge\left\rmoustache #1 \middle\rmoustache #2 \middle\lmoustache #3 \right\lmoustache}
+%\newcommand{\setmergeof}[3]{\setmerge\left\lfloor #1 \middle\lfloor #2 \middle\rfloor #3 \right\rfloor}