Re: Use of LWSP in ABNF -- consensus call

[Alexey Melnikov <[e-mail]>]

Dave Crocker wrote:

> On 5/14/2007 Lisa Dusseault wrote:
>
>> The IESG reviewed 
>> <http://www.ietf.org/internet-drafts/draft-crocker-rfc4234bis-00.txt> 
>> for publication as Internet Standard and would like to know if there 
>> is consensus to recommend against the use of LWSP in future 
>> specifications, as it has caused problems recently in DKIM and could 
>> cause problems in other places.
>>
>> Some discussion on this point already:
>>  - http://www1.ietf.org/mail-archive/web/ietf/current/msg46048.html
>>  - http://www1.ietf.org/mail-archive/web/discuss/current/msg00463.html
>>  - http://mipassoc.org/pipermail/ietf-dkim/2007q1/007295.html
>>  - 
>> https://datatracker.ietf.org/public/pidtracker.cgi?command=view_comment&id=66440  
>> (in this tracker comment, Chris Newman recommended to remove LWSP, 
>> but for backward-compatibility it's probably better to keep it and 
>> recommend against use)
>
> Folks,
>
> The current situation with elevating the ABNF document to full 
> Internet Standard is that Lisa has a Discuss hold on it, on behalf of 
> an IESG view that a warning note should be attached.
>
> Acting as an individual contributor, Chris Newman has offered the 
> following change to the document, as a possible means of resolving 
> things:
>
>> OLD:
>>         LWSP           =  *(WSP / CRLF WSP)
>>                        ; linear white space (past newline)
>> NEW:
>>         LWSP           =  *(WSP / CRLF WSP)
>>                        ; Use of this linear-white-space rule permits
>>                        ; lines containing only white space that are no
>>                        ; longer legal in mail headers and have caused
>>                        ; interoperability problems in other contexts.
>>                        ; Do not use when defining mail headers and use
>>                        ; with caution in other contexts.
>
I think this change is good enough, so I support it.