I just sent a message, which I meant to delete. So, if the thought seems incomplete, that is a correct observation.  I will complete the thought later.

 Paul Thompson

Professor and Senior Scientist
Director, Methodology and Data Analysis Center
Sanford Research
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----- Original Message ----
From: Will Robertson <[log in to unmask]>
To: [log in to unmask]
Sent: Thursday, August 20, 2009 2:25:13 AM
Subject: template customising

On 20/08/2009, at 2:32 AM, Joseph Wright wrote:

> Just a first thought, based on a better understanding of the concept. As
> you say, this might not be the best idea in the end.   I will probably
> write myself some (private) notes on the structure now I have a better
> picture of how things work, and see if anything else strikes me.

I think I see where my model of what's going on (particularly regarding collections) was slightly off-kilter. I agree we should delay discussing the mechanics (names, order of the args) until after we're solid on the fundamentals.

I've now got a new question. Following Joseph's examples, we might have something like \chapter which uses an instance 'chapter' of type 'sectioning'.

What should be done at the document design level to customise the look of the chapter headings? I don't think we want to have to redefine \chapter, so there are two options:

1. create a fresh instance called 'chapter' with the desired parameters,
2. "edit" the current 'chapter' instance.

The first option is what is necessary in, say, titlesec. I've got to admit it's not my favourite, because it requires you to possibly set or re-set a bunch of parameters that you were already happy with. (And you also have to know the name of the template it was produced with.)

Let's say then that I'd like to be able to edit the instance 'chapter'; is there any way to be able to do this?

I imagine markup like

    \EditInstance{sectioning}{chapter}% template is implicit!
        { ...keyvals... }

but I don't know if my desire for this construct illustrates a misunderstanding of mine of the system.


P.S.  I guess that something like the above \EditInstance would require a saved keyval list for the parameters used to generate the instance; however, I don't think that's an unacceptable use of memory.