public static JsonObject conv(VBox VB)
{
// all VBox implementations are classes - so this ID stuff works
var J_vb = new JsonObject();
J_vb["kind"] = "vbox";
J_vb["id"] = ID(VB);
J_vb["payload"] = VB.value() == null ? "null" : VB.value().ToString();
var J_preds = new JsonArray();
foreach (var pred in VB.preds())
{
J_preds.Add(ID(pred));
}
J_vb["preds"] = J_preds;
return(J_vb);
}