+local debug_traceback = debug.traceback;
+local unpack, select = unpack, select;
+pcall = function(f, ...)
+ local n = select("#", ...);
+ local params = {...};
+ return xpcall(function() f(unpack(params, 1, n)) end, function(e) return tostring(e).."\n"..debug_traceback(); end);
+end
+