--- /dev/null
+
+// huffware script: set comparator, by fred huffhines.
+//
+// provides a library of functions for managing sets.
+//
+// this script is licensed by the GPL v3 which is documented at: http://www.gnu.org/licenses/gpl.html
+// do not use it in objects without fully realizing you are implicitly accepting that license.
+//
+
+// API for set operations.
+//////////////
+integer SET_COMPARATOR_HUFFWARE_ID = 10020;
+ // a unique ID within the huffware system for this script.
+string HUFFWARE_PARM_SEPARATOR = "{~~~}";
+ // this pattern is an uncommon thing to see in text, so we use it to separate
+ // our commands in link messages.
+string HUFFWARE_ITEM_SEPARATOR = "{|||}";
+ // used to separate lists of items from each other when stored inside a parameter.
+ // this allows lists to be passed as single string parameters if needed.
+integer REPLY_DISTANCE = 100008; // offset added to service's huffware id in reply IDs.
+//////////////
+string DEFINE_SET_CMD = "#def-set";
+ // adds a new set or replaces existing one with same name. first parm is name of set,
+ // second and further parms are a list of elements that should be in the set. return
+ // value is a boolean for success.
+string REMOVE_SET_CMD = "#rm-set";
+ // trashes a named set. first parm is the name. returns a bool for success.
+string ADD_ELEMENTS_CMD = "#add-elem";
+ // adds more elements to an existing set. first parm is the name, second and more are
+ // the list of new elements. set must already exist. returns a bool for success.
+string CUT_ELEMENTS_CMD = "#cut-elem";
+ // removes a set of elements from an existing set. first parm is set name, second etc
+ // is list of elements to remove. set must already exist. returns bool.
+string INTERSECT_CMD = "#inter-set";
+ // reports the set of elements in the intersection of two sets. first and second parm
+ // are the set names. returns a wrapped list of elements that are common members of both sets.
+string UNION_CMD = "#union-set";
+ // returns the union of two named sets. results sent similar to intersection.
+string DIFFERENCE_CMD = "#diff-set";
+ // returns the difference of set A (parm 1) minus set B (parm 2). results are similar
+ // to intersection.
+string WHAT_MU_CMD = "#mu-set";
+ // returns one of the possibility values below to describe the relationship between
+ // two sets.
+string GET_SET_CMD = "#get-set";
+ // retrieves the contents of the set named in first parameter.
+string LIST_SET_NAMES_CMD = "#whichunz";
+ // retrieves the list of set names that exist.
+string CLEAR_ALL_CMD = "#clearall";
+ // throws out all set definitions.
+//////////////
+// joins a list of parameters using the parameter sentinel for the library.
+string wrap_parameters(list to_flatten)
+{ return llDumpList2String(to_flatten, HUFFWARE_PARM_SEPARATOR); }
+//////////////
+
+// these are the possible types of set relationships.
+string POSSIBILITY_ONE_MEANING = "one meaning (don gcig)"; // same set.
+string POSSIBILITY_THREE_POSSES = "proper subset (mu gsum)"; // set A contains set B or vice-versa.
+string POSSIBILITY_FOUR_POSSES = "four zones (mu bzhi)"; // non-null intersection, mutual non-null differences.
+string POSSIBILITY_MUTUAL_EXCLUDE = "mutually exclusive ('gal ba)"; // no members are shared between the sets.
+string POSSIBILITY_ERRONEOUS = "erroneous"; // not a valid request.
+
+// global variables...
+
+list all_sets; // a list of condensed lists.
+list set_names; // the names of each list in our list.
+
+integer DEBUGGING = TRUE; // produces noisy logging if true.
+
+// finds index of named list.
+integer find_set(string name_to_find)
+{
+ return find_in_list(set_names, name_to_find);
+}
+
+// ensures that the list does not contain duplicate members.
+list uniquify(list to_strain) {
+ integer i;
+ integer j;
+ for (i = 1; i < llGetListLength(to_strain); i++) {
+ string curr_i = llList2String(to_strain, i);
+ for (j = 0; j < i; j++) {
+ if (llList2String(to_strain, j) == curr_i) {
+ // this one is a duplicate! argh, remove it at index i.
+ to_strain = chop_list(to_strain, 0, i - 1)
+ + chop_list(to_strain, i + 1, llGetListLength(to_strain) - 1);
+ i--; // skip back since that element no longer exists.
+ j = i*3; // scoot j out to stop inner loop.
+ }
+ }
+ }
+ return to_strain;
+}
+
+// this version retrieves bare sets, not ones that are fluffed out from inclusions.
+list simple_get_set_by_index(integer index)
+{
+ if ( (index >= llGetListLength(set_names)) || (index < 0) ) return []; // out of range.
+ return llParseString2List(llList2String(all_sets, index), [HUFFWARE_ITEM_SEPARATOR], []);
+}
+
+
+// adds or replaces the set that is called "name".
+integer define_set(string name, list contents)
+{
+ contents = uniquify(contents);
+ integer curr = find_set(name);
+ if (curr >= 0) {
+ // an existing entry should be updated.
+ remove_set_by_index(curr);
+ }
+ all_sets += [ wrap_item_list(contents) ];
+ set_names += [ name ];
+//hmmm: may want to bomb out with false if too much space in use.
+ return TRUE;
+}
+
+// turns a combination of set linkages into the full set requested.
+// assumes that the index is pre-validated!
+list evaluate_set_components(integer index)
+{
+ string wrap = llList2String(all_sets, index);
+ list to_return = llParseString2List(wrap, [HUFFWARE_ITEM_SEPARATOR], []);
+ // check for our "equal to set X" case.
+ if (llGetListLength(to_return) == 1) {
+ string memb = llList2String(to_return, 0);
+ if (llGetSubString(memb, 0, 0) == "=") {
+//log_it("got a set assignment to other set called: " + llGetSubString(memb, 1, -1));
+ // we found a set that's equal to another. look up its equivalent.
+ index = find_set(llGetSubString(memb, 1, -1));
+ if (index < 0) return []; // unknown.
+ // got another set to check.
+ wrap = ""; to_return = [];
+ return evaluate_set_components(index);
+ }
+ }
+ if (llGetListLength(to_return) > 0) {
+ // scan for set includers.
+ integer i;
+ // must iterate forwards, since included sets can also include other sets.
+ for (i = 0; i < llGetListLength(to_return); i++) {
+ string curr = llList2String(to_return, i);
+ if (llGetSubString(curr, 0, 0) == "+") {
+ // found that this set includes another one. add in the second set,
+ // but chop out the element we just looked at.
+ to_return = chop_list(to_return, 0, i - 1)
+ + chop_list(to_return, i + 1, llGetListLength(to_return) - 1)
+ + simple_get_set_by_index(find_set(llGetSubString(curr, 1, -1)));
+ i--; // skip back so we don't omit the new element at i.
+ }
+ }
+ }
+ return to_return;
+}
+
+// retrieves the specified set from the list using its index.
+list get_set_by_index(integer index)
+{
+ if ( (index >= llGetListLength(set_names)) || (index < 0) ) return []; // out of range.
+ return evaluate_set_components(index);
+}
+
+// retrieves the specified set from the list using its name.
+list get_set_by_name(string set_name) { return get_set_by_index(find_set(set_name)); }
+
+// drops the set listed at the "index".
+integer remove_set_by_index(integer index)
+{
+ if ( (index >= llGetListLength(set_names)) || (index < 0) ) return FALSE; // out of range.
+ set_names = llDeleteSubList(set_names, index, index);
+ all_sets = llDeleteSubList(all_sets, index, index);
+ return TRUE;
+}
+
+// tosses the set called "set_name".
+integer remove_set_by_name(string set_name) { return remove_set_by_index(find_set(set_name)); }
+
+integer add_items(string name, list new_items)
+{
+ new_items = uniquify(new_items);
+ integer curr = find_set(name);
+ if (curr < 0) return FALSE; // unknown set.
+ list content = get_set_by_index(curr);
+ integer i;
+ for (i = 0; i < llGetListLength(new_items); i++) {
+ string new_item = llList2String(new_items, i);
+ integer found = find_in_list(content, new_item);
+ if (found < 0) {
+ // was not present yet so add it.
+ content += [ new_item ];
+ }
+ }
+ define_set(name, content);
+ return TRUE;
+}
+
+integer remove_items(string name, list dead_items)
+{
+ integer curr = find_set(name);
+ if (curr < 0) return FALSE; // unknown set.
+ list content = get_set_by_index(curr);
+ integer i;
+ for (i = 0; i < llGetListLength(dead_items); i++) {
+ string dead_item = llList2String(dead_items, i);
+ integer found = find_in_list(content, dead_item);
+ if (found >= 0) {
+ // was not present yet so add it.
+ content = llDeleteSubList(content, found, found);
+ }
+ }
+
+ define_set(name, content);
+ return TRUE;
+}
+
+// returns the union of two named sets.
+list set_union(string set_a, string set_b)
+{
+ integer where_a = find_set(set_a);
+ if (where_a < 0) return []; // not known.
+ integer where_b = find_set(set_b);
+ if (where_b < 0) return [];
+ list to_return = get_set_by_index(where_a);
+ list adding = get_set_by_index(where_b);
+ integer i;
+ for (i = 0; i < llGetListLength(adding); i++) {
+ string curr = llList2String(adding, i);
+ integer where = find_in_list(to_return, curr);
+ if (where < 0) {
+ // wasn't found in to_return, so add it.
+ to_return += [ curr ];
+ }
+ }
+ return to_return;
+}
+
+// returns the difference of two named sets.
+list set_difference(string set_a, string set_b)
+{
+ integer where_a = find_set(set_a);
+ if (where_a < 0) return []; // not known.
+ integer where_b = find_set(set_b);
+ if (where_b < 0) return [];
+ list to_return = get_set_by_index(where_a);
+ list adding = get_set_by_index(where_b);
+ integer i;
+ for (i = 0; i < llGetListLength(adding); i++) {
+ string curr = llList2String(adding, i);
+ integer where = find_in_list(to_return, curr);
+ if (where >= 0) {
+ // this item does exist in both, so remove it.
+ to_return = llDeleteSubList(to_return, where, where);
+ }
+ }
+ return to_return;
+}
+
+// returns the intersection of two named sets.
+list set_intersection(string set_a, string set_b)
+{
+ integer where_a = find_set(set_a);
+ if (where_a < 0) return []; // not known.
+ integer where_b = find_set(set_b);
+ if (where_b < 0) return [];
+ list to_return = [];
+ list a_con = get_set_by_index(where_a);
+ list b_con = get_set_by_index(where_b);
+ integer i;
+ for (i = 0; i < llGetListLength(b_con); i++) {
+ string curr = llList2String(b_con, i);
+ integer where = find_in_list(a_con, curr);
+ if (where >= 0) {
+ // this item does exist in both, so include in the result.
+ to_return += [ curr ];
+ }
+ }
+ return to_return;
+}
+
+// returns TRUE if minor is a proper subset of major.
+integer proper_subset(string minor_set, string major_set)
+{
+ integer where_a = find_set(minor_set);
+ if (where_a < 0) return FALSE; // not known.
+ integer where_b = find_set(major_set);
+ if (where_b < 0) return FALSE;
+ list min_con = get_set_by_index(where_a);
+ list maj_con = get_set_by_index(where_b);
+ // the list must be smaller to be a proper subset.
+ if (llGetListLength(min_con) >= llGetListLength(maj_con)) return FALSE;
+ // now make sure anything in the min is also in maj. if not, it's not
+ // a subset at all.
+ integer i;
+ for (i = 0; i < llGetListLength(min_con); i++) {
+ string curr = llList2String(min_con, i);
+ integer where = find_in_list(maj_con, curr);
+ if (where < 0) return FALSE;
+ }
+ // every item was present. yippee.
+ return TRUE;
+}
+
+// returns an assessment of the two sets in terms of the
+// possible relationships between them.
+string consider_mu(string set_a, string set_b)
+{
+ // firstly, validate these set names.
+ integer where_a = find_set(set_a);
+ if (where_a < 0) return POSSIBILITY_ERRONEOUS; // not known.
+ integer where_b = find_set(set_b);
+ if (where_b < 0) return POSSIBILITY_ERRONEOUS;
+ if (set_a == set_b) return POSSIBILITY_ONE_MEANING; // easy check.
+ // check whether they have any common members at all.
+ list inter = set_intersection(set_a, set_b);
+ if (inter == []) return POSSIBILITY_MUTUAL_EXCLUDE;
+ // see if one set is contained in the other.
+ if (proper_subset(set_a, set_b)
+ || proper_subset(set_b, set_a) ) {
+ return POSSIBILITY_THREE_POSSES;
+ }
+ // resign ourselves to loading up the sets to check equality.
+ integer len_a = llGetListLength(get_set_by_index(where_a));
+ integer len_b = llGetListLength(get_set_by_index(where_b));
+ if (len_a == len_b) {
+ // this is the only way they can be equivalent.
+ // simple interpretation of this currently...
+ list diff = set_difference(set_a, set_b);
+ if (diff == []) return POSSIBILITY_ONE_MEANING;
+ // so now, although they are of equal length, we know they are not
+ // equal sets.
+ }
+ // if our logic is correct, there is only one option left.
+ return POSSIBILITY_FOUR_POSSES;
+}
+
+// this should be invoked from the link_message event handler to process the requests
+// for whatever service this library script provides.
+handle_link_message(integer sender, integer huff_id, string msg, key id)
+{
+//log_it("link msg: " + (string)sender + " " + (string)huff_id + " msg=" + msg + " id=" + (string)id);
+ // separate the list out
+ list parms = llParseString2List(id, [HUFFWARE_PARM_SEPARATOR], []);
+
+ // we interpret the "msg" as a command.
+ if (msg == DEFINE_SET_CMD) {
+ string name = llList2String(parms, 0);
+ parms = llDeleteSubList(parms, 0, 0);
+ integer to_return = define_set(name, parms);
+ send_reply(sender, [ to_return ], msg);
+ } else if (msg == REMOVE_SET_CMD) {
+ string name = llList2String(parms, 0);
+ integer to_return = remove_set_by_name(name);
+ send_reply(sender, [ to_return ], msg);
+ } else if (msg == ADD_ELEMENTS_CMD) {
+ string name = llList2String(parms, 0);
+ parms = llDeleteSubList(parms, 0, 0);
+ integer to_return = add_items(name, parms);
+ send_reply(sender, [ to_return ], msg);
+ } else if (msg == CUT_ELEMENTS_CMD) {
+ string name = llList2String(parms, 0);
+ parms = llDeleteSubList(parms, 0, 0);
+ integer to_return = remove_items(name, parms);
+ send_reply(sender, [ to_return ], msg);
+ } else if (msg == INTERSECT_CMD) {
+ string name1 = llList2String(parms, 0);
+ string name2 = llList2String(parms, 1);
+ list to_return = set_intersection(name1, name2);
+ send_reply(sender, to_return, msg);
+ } else if (msg == UNION_CMD) {
+ string name1 = llList2String(parms, 0);
+ string name2 = llList2String(parms, 1);
+ list to_return = set_union(name1, name2);
+ send_reply(sender, to_return, msg);
+ } else if (msg == DIFFERENCE_CMD) {
+ string name1 = llList2String(parms, 0);
+ string name2 = llList2String(parms, 1);
+ list to_return = set_difference(name1, name2);
+ send_reply(sender, to_return, msg);
+ } else if (msg == WHAT_MU_CMD) {
+ string name1 = llList2String(parms, 0);
+ string name2 = llList2String(parms, 1);
+ string to_return = consider_mu(name1, name2);
+ send_reply(sender, [ to_return ], msg);
+ } else if (msg == GET_SET_CMD) {
+ string name = llList2String(parms, 0);
+ send_reply(sender, get_set_by_name(name), msg);
+ } else if (msg == LIST_SET_NAMES_CMD) {
+ send_reply(sender, set_names, msg);
+ } else if (msg == CLEAR_ALL_CMD) {
+ set_names = [];
+ all_sets = [];
+ send_reply(sender, [ 1 ], msg);
+ } else {
+ log_it("unknown set command: msg=" + msg + " id=" + (string)id);
+ }
+}
+
+
+//////////////
+//
+// from hufflets...
+
+// diagnostic hufflets...
+
+integer debug_num = 0;
+
+// a debugging output method. can be disabled entirely in one place.
+log_it(string to_say)
+{
+ debug_num++;
+ // tell this to the owner.
+ llOwnerSay(llGetScriptName() + "[" + (string)debug_num + "] " + to_say);
+ // say this on an unusual channel for chat if it's not intended for general public.
+// llSay(108, llGetScriptName() + "[" + (string)debug_num + "] " + to_say);
+ // say this on open chat that anyone can hear. we take off the bling for this one.
+// llSay(0, to_say);
+}
+
+//////////////
+
+// string processing hufflets...
+
+// the string processing methods are not case sensitive.
+
+// returns the index of the first occurrence of "pattern" inside
+// the "full_string". if it is not found, then a negative number is returned.
+integer find_substring(string full_string, string pattern)
+{ return llSubStringIndex(llToLower(full_string), llToLower(pattern)); }
+
+// returns TRUE if the "prefix" string is the first part of "compare_with".
+integer is_prefix(string compare_with, string prefix)
+{ return find_substring(compare_with, prefix) == 0; }
+
+//////////////
+
+// sim-related hufflets...
+
+// returns TRUE if the value in "to_check" specifies a legal x or y value in a sim.
+integer valid_sim_value(float to_check)
+{
+ if (to_check < 0.0) return FALSE;
+ if (to_check >= 257.0) return FALSE;
+ return TRUE;
+}
+
+// returns TRUE if the "to_check" vector is a location outside of the current sim.
+integer outside_of_sim(vector to_check)
+{
+ return !valid_sim_value(to_check.x) || !valid_sim_value(to_check.y);
+}
+
+//////////////
+
+// list processing hufflets...
+
+// locates the string "text" in the list to "search_in".
+integer find_in_list(list search_in, string text)
+{
+ integer len = llGetListLength(search_in);
+ integer i;
+ for (i = 0; i < len; i++) {
+ if (llList2String(search_in, i) == text)
+ return i;
+ }
+ return -1;
+}
+
+// removes the entry at "index" and instead inserts the list "to_insert"
+// at that position.
+list replace_entry(list to_modify, integer index, list to_insert)
+{
+ if (llGetListLength(to_modify) == 0) return to_insert; // special case for empty.
+ return llListReplaceList(to_modify, to_insert, index, index);
+}
+
+// returns the portion of the list between start and end, but only if they are
+// valid compared with the list length. an attempt to use negative start or
+// end values also returns a blank list.
+list chop_list(list to_chop, integer start, integer end)
+{
+ integer last_len = llGetListLength(to_chop) - 1;
+ if ( (start < 0) || (end < 0) || (start > last_len) || (end > last_len) ) return [];
+ return llList2List(to_chop, start, end);
+}
+
+//////////////
+
+// joins a list of sub-items using the item sentinel for the library.
+string wrap_item_list(list to_wrap)
+{ return llDumpList2String(to_wrap, HUFFWARE_ITEM_SEPARATOR); }
+
+// handles when blank strings need to come through the pipe.
+string wrap_blank_string(string to_wrap)
+{
+ if (llStringLength(to_wrap)) return to_wrap; // that one is okay.
+ return "\"\""; // return a quoted nothing as a signal for a blank.
+}
+
+// undoes a previously wrapped blank string.
+string interpret_blank_string(string to_unwrap)
+{
+ if (to_unwrap == "\"\"") return ""; // that was an encoded blank.
+ return to_unwrap; // no encoding.
+}
+
+// a simple version of a reply for a command that has been executed. the parameters
+// might contain an outcome or result of the operation that was requested.
+send_reply(integer destination, list parms, string command)
+{
+//log_it("reply set: " + dump_list(parms));
+ llMessageLinked(destination, SET_COMPARATOR_HUFFWARE_ID + REPLY_DISTANCE, command,
+ llDumpList2String(parms, HUFFWARE_PARM_SEPARATOR));
+}
+
+// returns a printable form of the list.
+string dump_list(list to_show)
+{
+ integer len = llGetListLength(to_show);
+ integer i;
+ string text;
+ for (i = 0; i < len; i++) {
+ string next_line = llList2String(to_show, i);
+ if (find_substring(next_line, " ") >= 0) {
+ // this guy has a space in it, so quote it.
+ next_line = "'" + next_line + "'";
+ }
+ text += next_line;
+ if (i < len - 1) text += " ";
+ }
+ return text;
+}
+
+//////////////
+
+default {
+ state_entry() { if (llSubStringIndex(llGetObjectName(), "huffotronic") < 0) state real_default; }
+ on_rez(integer parm) { state rerun; }
+}
+state rerun { state_entry() { state default; } }
+
+state real_default
+{
+ state_entry()
+ {
+// log_it("memory left " + (string)llGetFreeMemory());
+//hmmm: turn this into a report function.
+ }
+
+ link_message(integer sender, integer num, string str, key id) {
+ if (num != SET_COMPARATOR_HUFFWARE_ID) return;
+ handle_link_message(sender, num, str, id);
+ }
+}