\begin{verbatim}
drawbox = function (obj, color) {
    box (canvas, obj, obj.rect, ['color' = color;]);
};
redrawboxes = function () {
    local i;
    clear (canvas);
    for (i = 0; i < objnum; i = i + 1)
        drawbox (objarray[i], 1);
};
\end{verbatim}
