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Re: Is Content-type an RFC822 "structured header"?

1999-05-24 04:12:18
 Graham Klyne <GK(_at_)dial(_dot_)pipex(_dot_)com> writes:

At 10:43 21/05/99 GMT, Charles Lindsey wrote:

  Content-type: image/tiff; boundary=

It is completely legal.

Fine, but that still does not establish _exactly_ where folding may occur.

I beg to differ, in this case, because RFC822 (cited directly by the MIME
document) describes the lexical analysis of structured header fields:

       These symbols are:

                    -  individual special characters
                    -  quoted-strings
                    -  domain-literals
                    -  comments
                    -  atoms

Thus, folding is permitted between any pair of symbols indicated above.

Ah yes! But is a <token> one of those symbols that count as a "lexical
token"? The syntax for <token> first appeared in RFC2045 (or its
predecessor) AIUI, so it was not mentioned in RFC 822, and RFC 2045 is
silent on the issue.

The particular split we are discussing is legal because the object in
question is a <quoted-string>, but leave the DQUOTEs out of it, and is the
split then still legal?

Common sense says it should be, and that <token> should indeed be a
"lexical token", and Ned seems to agree. But it does not actually say so

BTW, I see that DRUMs uses the word "token" informally to discuss lexical
entities. Perhaps this is unwise in view of its use as a syntactic object
in RFC 2045.

Charles H. Lindsey ---------At Home, doing my own thing------------------------
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