Difference between revisions of "ListXxorY"

 LSL Portal

Function: list ListXnotY(list lx, list ly);

Returns a new list, composed of elements that were in either original script, but not both.

Note: This is not the same as getting rid duplicates by preserving just one of each duplicated item. It goes further, and removes both items.

```list ListXxorY(list lx, list ly) { // return elements that are in X or Y but not both
return ListXnotY( lx, ly) + ListXnotY( ly, lx);
}```

Example:

```list l1 = ["a","b","c","d"];
list l2 = ["a","1","b","2","c","3"];

list ListXxorY(list lx, list ly) { // return elements that are in X or Y but not both
return ListXnotY( lx, ly) + ListXnotY( ly, lx);
}

list ListXnotY(list lx, list ly) {// return elements in X list that are not in Y list
list lz = [];
integer i = 0;
integer n = llGetListLength(lx);
for (; i < n; i++)
if (llListFindList(ly,llList2List(lx,i,i)) == -1)
lz += llList2List(lx,i,i);
return lz;
}

default{
state_entry() {
llSay(0, "Elements that are in x list or y list but not both: " + llList2CSV(ListXxorY(l1,l2)));
//will say: d, 1, 2, 3
}
}```

Example 2 (Getting items added/removed from an inventory):

```list ListXxorY(list lx, list ly) { // return elements that are in X or Y but not both
return ListXnotY( lx, ly) + ListXnotY( ly, lx);
}

list ListXnotY(list lx, list ly) {// return elements in X list that are not in Y list
list lz = [];
integer i = 0;
integer n = llGetListLength(lx);
for (; i < n; i++)
if (llListFindList(ly,llList2List(lx,i,i)) == -1)
lz += llList2List(lx,i,i);
return lz;
}

list getInventory() {//method for returning a list of all inventory items in a list.
list InventoryList;
integer count = llGetInventoryNumber(INVENTORY_ALL);
string  ItemName;
while (count--)
{
ItemName = llGetInventoryName(INVENTORY_ALL, count);
if (ItemName != llGetScriptName() )
InventoryList += ItemName;
}
return InventoryList;
}

list saved_inventory_list;
default
{
state_entry()
{
saved_inventory_list = getInventory(); //Grab the list at state_entry to compare in future changes.
}

changed(integer change)
{
if(change & CHANGED_INVENTORY)
{
list new_inventory_list = getInventory();
list xory = ListXxorY(new_inventory_list,saved_inventory_list); //Comparing new inventory with old one.
string item_changed = llList2String(xory, 0); //xory list will always be a size of 1 in changed event.

//If the new inventory is greater than the saved inventory then it means an item hs been added, otherwise removed.
if(llGetListLength(new_inventory_list) > llGetListLength(saved_inventory_list))
{