ietf-nntp newsgroup production
cheekai at SoftML.net
Thu Jul 27 06:17:10 PDT 2000
Thanks for including USEFOR definitions, Charles.
>> In <Pine.LNX.3.93.1000726124639.1130C-100000 at one.softml.net> Chin Chee-Kai <cheekai at SoftML.net> writes:
>> >+ The conventions as defined in RFC822 are used. In addition, the
>> >+ notation "\", when used in the production rules, denotes exclusion.
>> No, I son't think you want to invent a special notation just so you can
>> use it in one situation.
Well, I can see why you say that. It's a convenience suggestion.
Alternatively, we could list the range of characters covered in
"parameter \ DOT" and name it as a new character set for use in
>> >+ argument = parameter ; excluding sequence ".."
>> >+ ;;; original production :: augument = parameter ; excluding sequence ".."
>> But since 'argument' is not used elsewhere in the syntax, why not leave it
Because "argument" is used elsewhere in the descriptions in the
earlier sections. The intro paragraph of Section 13 says so.
Someone tell me my interpretation is wrong.
>> >+ newsgroup = newsgroup-segment *(DOT newsgroup-segment)
>> >+ newsgroup-segment = parameter \ DOT
>> >+ DOT = %x2E
>> The USEFOR syntax is:
>> newsgroup-name = component *( "." component )
>> component = component-start
>> *( component-start / component-other )
>> component-start = Un-lowercase / Un-digit
>> Un-lowercase = <Unicode Letter, Lowercase> /
>> <Unicode Letter, Other>
>> Un-digit = <Unicode Number, Decimal Digit> /
>> <Unicode Number, Other>
>> component-other = "+" / "-" / "_"
>> The complication arises because of the UTF-8 and a desire to exclude
>> upparcase letters. I do not think we need quite so much complication in
>> this document, so I would suggest:
>> newsgroup = component *( "." component )
>> component = <a sequence composed of letters, digits,
>> "+", "-" and "_">
Ah, the USEFOR syntax doesn't quite work. The "component-start"
production does not allow "-" to be used as a non-starting character
in the first component of a newsgroup reference. Currently, just off
my neighborhood ISP's news server, I already see
as counter-examples. So Charles, your suggestion is fine, except
you gotta add the necessary definitions for "letters" and "digits"
(though obvious), and also the 0x80-0xFF characters for UTF-8
multi-lingual newsgroup references.
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