Subj : Re: help with ebnf for ebnf newbie?
To   : comp.programming
From : pantagruel
Date : Thu Sep 15 2005 03:43 am

'"callid=" is followed by a comma and "callfrom=" is not. '

oops, typo there.

"Can <value-list> be empty? "
Theoretically as none of the fields are required but I think for a good
order it will be specified that it cannot be empty.

but if:


<value-list> ::= <name-value-pair> |
                 <name-value-pair> "," <value_list>

<name-value-pair> ::= name "=" value

then won't that allow

callid=wotcha



so it should be:

<value-list> ::= <name-value-pair> |
                 <name-value-pair> "," <value_list>

<name-value-pair> ::= name "=" value



Values can include spaces, names can theoretically include spaces
however I think it would make sense to limit spaces as well where names
are concerned.


" you should probably
concatenate instead since you seem to want both callid and callfrom on
the same line.
"
yeah, this is the part where I have the biggest trouble, there is a
list of known names none of which are required. Unfortunately don't
know how to represent these names as optional, with the possibility of
other user defined names and values.



for example before where I said:

callid=wotcha,callfrom=whoyathunk,testing=othervalue


it should also just as well match

callfrom=whoyathunk,testing=othervalue,callid=wotcha

.