Re: [PING] Please explain: wl-summary-resend-use-cache

[David Abrahams <dave@boostpro.com>]

At Mon, 11 Jan 2010 11:15:20 -0800,
Erik Hetzner wrote:
> 
> > > info wanderlust sez:
> > > 
> > >   `wl-summary-resend-use-cache'
> > >        The initial setting is `nil'¡£If non-nil, messages are resend using
> > >        cache even in the offline status. Note that if you use cache, the
> > >        message identity is not guaranteed.
> > > 
> > > while `M-x describe-variable <RET> wl-summary-resend-use-cache' sez:
> > > 
> > >   *Non-nil to enable offline resending by using file cache.
> > >   Note that strict message identity is not guaranteed when cache is used.
> > > 
> > > The former makes it sound as though, if wl-summary-resend-use-cache is
> > > nil, you can resend when offline, but it won't "use the cache," whatever
> > > that means.  The latter makes it sound like you can't resend when
> > > offline if wl-summary-resend-use-cache is nil.
> > > 
> > > Neither description explains why the cache is relevant to resending when
> > > offline, and neither explains what it means for message identity to be
> > > guaranteed.  Could someone clarify these points (on the list and in the
> > > docs)?
> > 
> > Thank you!
> 
> Hi -
> 
> I never use resend functionality. It is only for bounced messages, as
> far as I know. 

I need it from time to time.

> I have never seen it discussed, so I think it is a little used
> feature.
> 
> In any case, docs could read, perhaps more clearly:
> 
>   If non-nil, messages are resent using the cache when offline. If
>   nil, trying to resend a message when offline will fail. Note that if
>   non-nil, the message identity is not guaranteed.
> 
> Does that make more sense? 

That description leaves me with all the same questions.  Let me try to
bullet them:

1. What does it mean to "use the cache" to send a message when offline?
2. What does it mean to guarantee message identity?

> I am not sure myself why message identity
> is not guaranteed, presumably something is not stored in the cache
> which is necessary to preserving the right Message-Id when resending a
> bounced message.

So your answer for #2 is that guaranteeing message identity means the
resent message will have the same Message-ID as the original?

And for #1?

-- 
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BoostPro Computing
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