[Twisted-Python] Woven page instances deferring to each other...

[Mary Gardiner]

On Wed, Oct 08, 2003, Mary Gardiner wrote:
> Assuming you meant "I'd like totally different HTML generated if
> there is an error state" you probably do want macros or something like
> them. The best documentation I've seen on this is here:
> http://twistedmatrix.com/pipermail/twisted-python/2003-June/004662.html

Followup...

A nicer solution may be to have the parent Page (by this I mean
http://example.com/bob/ is a parent and http://example.com/bob/result/
is a child -- parents in the URL structure) do the check and return an
object of a different Page class, something like:

class MyParentPage(page.Page):

    def getDynamicChild(self, name, request):

        if error_condition_1:
            return ErrorPage1()
        elif error_condition_2:
            return ErrorPage2()
        else:
            return NormalChildPage()

If there's any way you can determine if the error has happened before
the child page starts rendering, then I suspect it would be nicer to do
the error check at child creation time, rather than when the child
renders.

You can then use macros for something like their normal function: which
is defining the bits of pages that look mostly the same across lots of
pages (navigation bars and the like).

-Mary