registry.add("iset", new ISet());
registry.add("iacc", new IAcc());
registry.add("rlist", new RList());
registry.add("rmk", new RMk());
registry.add("rget", new RGet());
registry.add("rrec", new RRec());
registry.add("xacc", new XAcc());
registry.add("xprd", new XPrd());