ietf-822
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Re: UTF-8 over RFC 2047 (Re: Call for Usefor to recharter)

2003-01-14 15:32:56

Dave Crocker writes:
paying attention to the installed base requires worrying about
compatibility with what has been established practise, not what
"might" work or what is "frequently" available.

RFC 2047 makes a blatantly incompatible change to the semantics of
various sequences of bytes. It defends this incompatibility by saying

   The syntax of encoded-words is such that they are unlikely to
   "accidentally" appear as normal text in message headers.

Why aren't you screaming about the difference between ``unlikely to''
and ``guaranteed to never''? This isn't a safe extension that merely
assigns semantics to previously prohibited behavior (such as ``8-bit
data is UTF-8''). This is an _incompatible change_ to the semantics of
perfectly _valid_ behavior. Why is that okay? What level of potential
collateral damage are you willing to tolerate?

---D. J. Bernstein, Associate Professor, Department of Mathematics,
Statistics, and Computer Science, University of Illinois at Chicago