Not to be overly picky, but software source code is written by humans, for humans (and finally for compilers). I'm not sure anyone writes SIP messages by hand or creates them to make them easier to read. On top of that, if a compiler runs into an issue where something's ambiguous, it can simply error out. An automated piece of software doesn't have this luxury; rejecting a message that someone thinks is fine just ends up making your software "incompatible", no matter what the spec says.
At any rate, as you note, it's somewhat a pointless discussion since nothing's going to change. I'm just terribly curious as to why these decisions were made, not back in the 70s, but why they were kept going forwards. -Michael -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Paul Kyzivat Sent: Wednesday, March 26, 2008 3:30 PM To: Iñaki Baz Castillo Cc: [email protected] Subject: Re: [Sip-implementors] Why SIP abnf is so permissive??? You could make the same argument about C or Java. They would (arguably) be easier to compile if you only allowed whitespace in a much more restricted set of places. I think this is more a matter of how the syntax is described, rather than what it allows. Most parsers that I know of distinguish lexical processing from parsing. If you do that, each becomes simpler. But the 3261 syntax in ABNF encompasses both, and is more complex as a result. I think you might find that if you manually transformed the syntax, splitting off a lexical phase, you wouldn't see the same complexity. In any case, the form of the syntax is now institutionalized and won't be changed any time soon. Paul Iñaki Baz Castillo wrote: > El Wednesday 26 March 2008 14:50:45 Iñaki Baz Castillo escribió: > >> Am I the only who thinks that SIP could be really much easier than it's now >> just by doing it less permissive? > > More things: > > > - Why line folding allows any number of space or tab at the beggining of the > line instead of just a single space? > ------------------------------------------------------- > Subject: This is the > subject in > line > folding > ------------------------------------------------------- > In fact, when it's rebuilt in the UAS any number of spaces at the line start > is converted into a single space: > ------------------------------------------------------- > Subject: This is the subject in line folding > ------------------------------------------------------- > > > - Why host:port allows any number of spaces, tabs, CRLF between "host" and ":" > and between ":" and "port"? > ------------------------------------------------------- > 192.168.1.33 > : > 5061 > ------------------------------------------------------- > Wouldn't it be much easier if there couldn't be any space between them? > ------------------------------------------------------- > 192.168.1.33:5061 > ------------------------------------------------------- > > > Best regards. > _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
