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Date:         Thu, 20 Aug 2009 16:55:13 +0930
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From: Will Robertson <wspr81@GMAIL.COM>
Subject: template customising
To: LATEX-L@LISTSERV.UNI-HEIDELBERG.DE
Precedence: list
Status: R

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.

Will

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.