ListXandY

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

This function examines two lists, and returns a new list composed of the elements that both lists have in common.

See also: Lists

list ListXandY(list lx, list ly) {// return a list of elements common to both lists
    list lz = []; integer x;
    for (x = 0; x < llGetListLength(ly); x++) {
        if (~llListFindList(lx,llList2List(ly,x,x))) {
            lz = lz + llList2List(ly,x,x);
        }
        else {
            ;
        }
    }
    return lz;
}

Example:

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

list ListXandY(list lx, list ly) {// return a list of elements common to both lists
    list lz = []; integer x;
    for (x = 0; x < llGetListLength(ly); x++) {
        if (~llListFindList(lx,llList2List(ly,x,x))) {
            lz = lz + llList2List(ly,x,x);
        }
        else {
            ;
        }
    }
    return lz;
}

default{
   state_entry() {
      llSay(0, "The two lists have the following items in common: " + llList2CSV(ListXandY(l1,l2)) );
      //will say: a, b, c
   }
}

Posted with the kind permission of Very Keynes, who originated this script June 2007 in the SL scripters forum http://forums-archive.secondlife.com/54/e4/194138/1.html