Hi,

In message "Re: nil encoding as synonym for binary encoding"
    on Fri, 11 Jan 2008 13:43:37 +0900, David Flanagan <david / davidflanagan.com> writes:

|This is an incompatible change to the original 1.9.0 release: it means 
|that we can no longer use force_encoding(nil) as a way of saying "this 
|string has no encoding--I want to see the unencoded bytes".    Instead 
|we're forced to use something longer like force_encoding("binary") or 
|force_encoding(Encoding::BINARY).
|
|The ability to use nil as a synonym for ASCII-8BIT/BINARY allowed it to 
|mean "no encoding".

I don't think there's no string in Ruby without encoding.  Every
string has their own encoding.  Allowing nil is pretty easy, but if it
encourage the false conception (like you had), it might be better to
remove it from long range view.  Let me think.

							matz.
p.s.
I am awfully sorry for the last minute changes like this anyway.