🚀 go-pugleaf

In article <643@cdx39.UUCP> jc@cdx39.UUCP (John Chambers) writes:

>>      route       =  1#("@" domain) ":"           ; path-relative
>> =====================^ Indicates a comma separated list (see section 2.7)

> Say what?  According to my eyeballs, and to this editor (vi), there are
> no commas at all within these lines.  Note that the original message wasn't
> asking for the syntax of things like routes or domains; he was asking for
> the part that described commas.  You seem to have quoted all the relevant
> stuff except the answer to his question.

And you seem to have shot from the hip before READING the quoted poster.
It even SAYS "comma separated list"...  With POINTERS and STARS and such.
Sheesh.  The full reference is section 2.7 (page 4) of RFC822:

2.7 #RULE:  LISTS

>	A construct "#" is defined, similar to "*", as follows:

>	<l>#<m>element

> indicating at least <l> and at most <m> elements, each separated
> by one or more commas (",").  This makes the usual form of lists
> very easy; a rule such as '(element *("," element))' can be shown
> as  "1#element".  Wherever this construct is used, null elements
> are allowed, but do not contribute to the count of elements
> present.  THat is, "(element),,(element)" is permitted, but
> counts as only two elements.  Therefore, where at least one ele-
> ment is required, at least one nun-null element must be present.
> Default values are 0 and infinity so that "#(element)" allows any
> number, including zero;  "1#element" requires at least one; and
> "1#2element" allows one or two.

It is interesting to consider the implications of the null element stuff.
Seems like:

        Yours Truly <@wiscvm.wisc.edu,,,,,@umd2.umd.edu:zben@umd5>

is legal (gack).  Fascinating...

> BTW, what does the comma notation *mean*?  Is it a list of hosts to send
> the mail to, i.e., a route?  Is is a list of alternatives?  Is it a list
> of other places the mail can be delivered to if host3 isn't available?
> To use it correctly, you have to know more than the syntax; you have to
> understand the semantics.  So far, I have seen a lot of people toss the
> syntax around, without any hint as to what it means.  How about someone
> posting that portion of the RFC?

I diligently searched all of 822 and could not find one example.  However,
those familiar with the companion RFC821 and further having decent pattern
matching neuro-ware may realize that the out-of-band back-path maintained 
in accordance with section 3.6 on page 14 is exactly the same animal:

> 3.6.  RELAYING

> The forward-path may be a source route of the form
> "@ONE,@TWO:JOE@THREE", where ONE, TWO and THREE are hosts.  This
> form is used to emphasize the distinction between an address and a
> route.  The mailbox is an absolute address, and the route is 
> information about how to get there.  The two concepts should not
> be confused.

I believe a little study of the rest of the section will make the 
semantics more than clear.

> [To satisfy the requirement that my text lines outnumber the quoted lines.]

Gee, guy, I take the time to trim quoted text down to minimal form.  That
is what the software is trying to enforce by counting your lines.  
-- 
                    umd5.UUCP    <= {seismo!mimsy,ihnp4!rlgvax}!cvl!umd5!zben
Ben Cranston zben @ umd2.UMD.EDU    Kingdom of Merryland UniSys 1100/92
                    umd2.BITNET     "via HASP with RSCS"