string llDumpList2String(list src, string separator)
Concatenates all items in the list src
into a single string, placing the specified separator
performs the opposite function.
If you want to add to what comes out, it seems to Follow in this format
list foo = ["Bear","Cat","fish","bird"];
llSay(0,"11" + llDumpList2String(foo,"22+33") + "44");
//comes out 11Bear22+33Cat22+33fish22+33bird44
See also llList2CSV
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