Re: [Nmh-workers] Future directions for nmh

[Jon Steinhart]

Ken Hornstein writes:
> >As you might guess if you've been on this mailing list forever, I'd
> >really like to see a better user interface for reading attachments.
> >In short, I'd like to keep track of the "current part", and have
> >"next part" and "previous part" options to show.  There should be
> >a flag that allows switching to the next/prev message if next/prev part
> >runs out of parts.  To me, this would be so much better than having to
> >do a mhlist and then type part numbers.  I looked at doing this years
> >ago and got stopped by dealing with the parsing stuff.  There should
> >also be an option to scan that lists the parts in messages.  So if the
> >parser is redone maybe it will be done in such a way to support this.
> 
> So I think those things would be possible.  The current thinking is that
> the message parser would be 'lazy', in that any time a message is opened
> you're going to get the complete headers, and then parse the body if you
> ask for it via the API.  I'm not convinced 'scan' is the right tool to
> list message parts; we'd have to think about how that would work.  I would
> also caution you that to completely parse a message's MIME structure you
> need to read the whole thing; maybe this wouldn't be so bad on IMAP since
> you could simply ask the IMAP server for the message's MIME structure
> (hopefully once it built the structure it would be cached on the server).
> My point is that you had a scan format that showed MIME structure, the
> performance would probably be significantly impacted.
> 
> But I have to ask about the idea of going from one MIME part to another;
> do you really want to do that?  I can only go on how I interact with
> messages; almost always, I want to read the text part, and then interact
> in some other way with non-text parts (generally save them or open them
> with another tool).  'Stepping' through MIME parts is just not something
> that makes sense to me.  Sure, I want to make it as flexible as possible
> and just because something doesn't make sense to me doesn't mean it shouldn't
> be possible!  But I do want to understand the usage case completely.  It
> occurs to me that if we do it right we could make it easy to accomplish
> this via scripts, which strikes me as more of the 'MH way' (basically,
> provide the tools to interrogate the MIME structure of a message and then
> go to the "next" MIME part).

Well, it depends on the message.  Sometimes I get a message with 20 photos
attached.  I just want to be able to easily go from one to the next without
having to type their part number.
 
> >I am emboldened by David's posting regarding add-hook, etc.  Didn't know
> >that anybody actually used that stuff other than me.  The hook stuff was
> >an expedient hack on my part, and it's not really as robust as it could
> >be.  I would like to see it made more of an integral part of nmh as
> >opposed to the add-on hack that I did.
> 
> Well ... do you have any thoughts there?  I mean, seems like it's integrated
> pretty well now.  Probably the two things that are lacking is a man page
> and tests for the test suite (more people might know about it if the
> various commands had pointers saying which hooks were invoked).

There is no real error recovery.  I thought that I had added it to the man
pages but it was a long time ago and don't remember now.

> The bottom line is that all of this is a large amount to bite off at once.
> My first thought is to do the MIME parser, but keep the rest of everything
> as close to the same as possible.  Then we can talk about different mailstores

I agree, I just would like to keep these other things in mind while doing the
parser so that they're not precluded later.

Gotta run, be back in touch on Monday.

Jon