On 8/29/11 9:44 PM, Eric Burger wrote:
Yes, and...
I would offer that for most cases, If Y then MUST X or If Z then MUST NOT X
*are* what people usually mean when they say SHOULD. In the spirit of Say What
You Mean, a bare SHOULD at the very least raise an ID-nit, suggesting to the
author to turn the statement into the if Y then MUST X or if Z then MUST NOT X
form. Being pedantic and pedagogic:
SHOULD send a 1 UNLESS you receive a 0
really means
UNLESS you receive a 0, one MUST send a 1.
My vision of the UNLESS clause is not necessarily a protocol state, but an
environment state. These are things that I can see fit the SHOULD/UNLESS form:
SHOULD send a 1 UNLESS you are in a walled garden
SHOULD flip bit 27 UNLESS you have a disk
SHOULD NOT explode UNLESS you are a bomb
are all reasonable SHOULD-level statements.
I would offer that ANY construction of SHOULD without an UNLESS is a MAY.
Eric. Put down the axe and step away from the whetstone. Here, I'll give
you some text from RFC 3265 to mull.
deactivated: The subscription has been terminated, but the subscriber
SHOULD retry immediately with a new subscription. One primary use
of such a status code is to allow migration of subscriptions
between nodes.
Let's examine this use of "SHOULD." If the subscriber doesn't
re-subscribe, is it an interop issue? No.
Is it in the interest of the implementation to re-subscribe? Yes. At
least, under most circumstances. Otherwise, they won't get the state
change notifications they want.
Are there cases in which it makes sense for the subscriber _not_ to
re-subscribe? Yes, I'm sure there are. It's conceivable that the client
happens to be shutting down but hasn't gotten around to terminating this
particular subscription yet. But any such exceptions are highly
implementation-dependent. Listing them would be useless noise to the
reader, and senseless text creation for the author.
Does "SHOULD" get abused by some authors in some documents? Of course it
does. But your crusade to throw out a useful tool just because it has
been misused on occasion is an extreme over-reaction. I like this tool.
I use this tool. If you see people misusing it, slap them.
But don't ban the tool.
/a
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