"Hal E. Fulton" <hfulton / austin.rr.com> writes: > Well, if you look at the << method, it just says it takes "anObject"... > I don't recall seeing anything about to_str (or to_s) anywhere... It's talked about on 382, under to_str. I'm not sure just how many methods rely on to_str to convert their arguments: I suspect there's a fair number. We recently discovered that $/ for example can only be assigned from something that implements to_str. Dave