val simpleNode = node.getSimpleNodesByName(keyValue.key);
if(simpleNode !== null && !simpleNode.empty) {
checkState(simpleNode.size <= 1,"Only one simple node for key $s is allowed in node $s",keyValue.key,node);
val simpleNode = node.getSimpleNodesByName(keyValue.key);
if(simpleNode !== null && !simpleNode.empty) {
checkState(simpleNode.size <= 1,"Only one simple node for key $s is allowed in node $s",keyValue.key,node);