Some half decent stuff in here, but I heavily disagree with changing the output of toString. That might cause problems if someone is expecting one output, but

Some half decent stuff in here, but I heavily disagree with changing the output of toString. That might cause problems if someone is expecting one output, but the new version creates something new. I don't see a reason why they couldn't have just added a new function functionCode() or something similar. It would give people the functionality they want, without destroying backwards compatibility.