bear writes:
> I want to know something: what does a string containing an
> unpaired surrogate mean?  What is represented by it?  How
> can anything handle it sensibly in rendering or reading or
> writing?

An unpaired surrogate can be displayed with whatever the local
"unrenderable" character is. A string containing an unpaired surrogate
has a localized error in it.

Surrogates should never appear (IMHO) in high-level (i.e.,
non-transcoding) code except in cases abuse, as you point out.

> So I don't regard it as being at all important, or even
> appropriate, to allow unpaired surrogates in strings.

It doesn't strike me as at all important, FWIW, to spend any effort
explicitly enforcing a requirement that a string not contain
surrogates. They are designed, after all, to "just work" in
implementations that are not surrogate aware.

--
Tom Emerson                                          Basis Technology Corp.
Software Architect                                 http://www.basistech.com
  "Beware the lollipop of mediocrity: lick it once and you suck forever"