question

Hello @Vns,

The only thing you are missing with implementing what you found is you need to change your MatchedOrder and Order to be integer variables instead of strings and use 0 instead of a blank string.

/**Custom Code*/
treenode current = ownerobject(c);
treenode item = param(1);
int port =  param(2);
int MatchedOrder = current.MatchedOrder;

if (MatchedOrder != 0) {
    //We previously matched an item so pull the matching order from the other queue
    if (item.pallet_id == MatchedOrder) {
        current.MatchedOrder = 0;
        return 1;
    }
    return 0;
}
 
int Order = item.pallet_id;
//Search the opposite queue for the same order
int otherPort = port % 2 + 1; //Grab the other port rank so we look at the other queue
treenode queue = current.as(Object).inObjects[otherPort];
for (int i = 1; i <= queue.subnodes.length; i++) {
    if (queue.subnodes[i].pallet_id == Order) {
        //Found a matching order, save the order on a label
        current.MatchedOrder = Order;
        //Now pull the item that just entered the original queue
        return 1;
    }
   
}
//No matches, pull nothing
return 0;

test1_1.fsm