<<< native
[ EArray
    [ AlignCenter , AlignCenter ]
    [ [ [ ESymbol Accent "\8592" ] , [ ENumber "1" ] ]
    , [ [ EText TextNormal "a long cell" ] , [ ENumber "1" ] ]
    ]
]
>>> eqn
matrix{
ccol{ <- above {roman "a long cell"} }
ccol{ 1 above 1 }
}