Re: Mailing List Last Call for 2822 update internet-draft

In message <[email protected]>, Alan Barrett 
<[email protected]> writes
>
>On Mon, 30 Jul 2007, Alan Barrett wrote:
>> > It sure was. Comments and folding white space were allowed between
>> > any two tokens in RFC 822. And since the syntax for zone was:
>> >
>> >                         ("+" / "-") 4DIGIT
>> >
>> > a comment was allowed between those two. I don't know how to read
>> > 3.1.4 and 3.4.3 in RFC 822 and not come up with that interpretation.
>>
>> Yes, you are correct.
>
>Hang on...  "+" and "-" are not in the list of special characters that
>RFC822 section 3.1.4 says are used to delimit tokens.

No, but quote marks are in the list of specials, "+" and "-" are 
quoted-strings.

>  So I would say
>that, given input like "+0000", the sign and the digits together make
>up an "atom" per the description in section 3.1.4 and the grammar in
>section 3.3.  The ( ("+" / "-") 4DIGIT ) production in the grammar in
>section 5.1 is looking inside a single token, not looking at two tokens.

Disagree, a quoted-string is a token

RFC822 3.1.4:

>   These symbols are:
>
>                     -  individual special characters
>                     -  quoted-strings
>                     -  domain-literals
>                     -  comments
>                     -  atoms
>

So the "+", "-" and 4DIGIT are distinct tokens in RFC822, two quoted 
strings and an atom.

>
>For another example of grammar productions that look inside a single
>lexical token, consider RFC822's definitions of quoted-pair and
>quoted-string.  I hope nobody argues that the "\" and the CHAR in a
>quoted-pair are two tokens and that LWSP is allowed between them.
>

Agreed, because a quoted-string is a single token.


Regards

-- 
Paul Overell         Internet Platform Development Manager, Thus plc