[mail-vet-discuss] current syntax

[Michael Thomas]

Murray S. Kucherawy wrote:
> Michael Thomas wrote:
>>
>> What's the big deal about having cfws after every tag/value? That makes
>> each element completely symmetric and thus easier to parse.
> As Tony mentioned, the current ABNF already allows that; there's CFWS 
> just about everywhere between tokens.
>
>> Why? It used to be last. I never lost sleep over it one way or the
>> other. Making the order irrelevant definitely makes the parsing
>> easier though.
> Since it was Tony that advocated for that change, I'll let him defend 
> it... ;)
>
> My first guess though would be that each result is contained between 
> ";" characters, so you could easily skip forward looking for one you 
> want without having to consume entire blocks of the header.

The concern I have with making ws the delimiter is that in real life, is 
that
some things in the mail stream will sometimes rewrap lines, and they 
sometimes
do it at non-ws boundaries. I really wish that we had made dkim immune to
fws insertions by keeping nowsp for headers, but illegal for the body. 
making
auth-res immune to the same manglers seems like a prudent thing, imo.

       Mike, gnu mailman's python smtp library being a prime culprit