\def\sqntype#1{\ensuremath{seq.#1}}
\def\xsqntype#1{\ensuremath{seq.#1}}
\def\xnil{\ensuremath{\varepsilon}}

\def\xsqn#1{\ensuremath{\langle{#1}\rangle}}
\def\xconsftor{\ensuremath{\triangleleft}}
\def\xcons#1#2{\ensuremath{#1\xconsftor #2}}

\def\xsnocftor{\ensuremath{\triangleright}}
\def\xsnoc#1#2{\ensuremath{#1\xsnocftor #2}}

\def\hsconsftor{\ensuremath{\pmb{:<\mid: }}}
\def\hscons#1#2{#1\hsconsftor #2}

\def\xcatftor{\ensuremath{\pmb{\,\hat{ }\,\hat{ }\,}}}
\def\xcat#1#2{\ensuremath{#1\xcatftor #2}}

\def\hscat#1#2{\ensuremath{#1 :\hat{ }: #2}}

\def\xsubsqnftor{\ensuremath{\sqsubseteq}}
\def\xsubsqn#1#2{\ensuremath{#1\xsubsqnftor #2}}


