Opaque

> Dave Kristol wrote:
> But you might want a separate Opaque: value for each of Session-ID
> and WWW-Authenticate:.  Better to leave them as attributes of a
> particular header, IMO.

It's certainly true that one could have an 'opaque' field defined,
usefully, for almost any kind of header (different languages, for
example, or different dates, or modified by dates, or dependent on
URI, and so on).

But it's over-heavy to define these as sub-fields of every kind of
header, rather than sub-classes of opaque data (if the latter really
are needed).

Mike Cowlishaw