local methods = {}; local resolver_mt = { __index = methods }; -- Find the next target to connect to, and -- pass it to cb() function methods:next(cb) if #self.targets == 0 then cb(nil); return; end local next_target = table.remove(self.targets, 1); cb(unpack(next_target, 1, 4)); end local function new(targets, conn_type, extra) return setmetatable({ conn_type = conn_type; extra = extra; targets = targets or {}; }, resolver_mt); end return { new = new; };