From: "S. Robert James" <srobertjames@...>
Date: 2007-02-23T08:00:08+09:00
Subject: puts nil

puts nil outputs "nil".  Shouldn't it output "" (ie, nothing), which
is nil.to_s?

RDoc (for IO#print, referenced by #puts):
Objects that aren't strings will be converted by calling their to_s
method