[albatross-users] Access to current/other page objects/modules

[Gregory Bond]

I'm trying to work out a way to do semi-automated navigation.  I'm using a
file-based session and page classes, tho something portable to page modules
wouldn't hurt.

The actual navigation I can do with a page base class, and a nav_to[] class
variable for each page class that the base class page_process() can look at.

But I can't work out a way to generate a nav bar HTML automatically.  Ideally, 
I'd like each page class to have a description, which might depend on the 
current local context / session, and then have a single tag/function/macro/
something that can be called from a template and can:
 - find the class object for the current page
 - for each of the class objects mentioned in the nav_to[] member:
	- find the class object for this destination page
	- find the description of this destination page after possibly 
		substituing stuff from the current session with al-value etc
	- Generate a <al-a> tag with the appropriate description.

So given something like:
	class Start(PageBase):
		name='start'
		nav_desc='Start Again'
		#...
	class HomeAddress(PageBase):
		name='homeaddr'
		nav_to=['start', 'workaddr']
		nav_desc = 'Update Home Address for <al-value expr="client">'
		#...
	class WorkAddress(PageBase):
		name='workaddr'
		nav_to=['start', 'homeaddr']
		nav_desc = 'Update Work Address for <al-value expr="client">'

then I could from homeaddr.html call a macro / custom tag that would produce
	<al-a href="?start=1">Start Again</al-a>
	<al-a href="?workaddr=1">Update Work Address for BOND</al-a>

But I can't work out a way of doing this that has access to all the pieces 
needed....  which (afaict) amounts to 
 - the current session (for substituting into descriptions)
 - the current page class object ("self" in page_display())
 - the list of page objects (hidden inside the current application object?)
and is callable from the middle of a HTML template.

Any ideas?