>> If I understood you correctly you want something along Stackoverflow,
>> where you see the resulting HTML along when you type.
>
> No, I want the simpler thing: I click on some text and get a text
> area where I can edit the wiki source. No live preview necessary.
That's far more complicated.
Have a look at PRHaloRenderer in Pier-EditorEnh this is somehow
similar. This adds a halo around each structure as it is rendered to
HTML. In your case you would do something similar but render an
in-place editor around each paragraph.
Some versions of Pier back in 2005 or 2006 had such a functionality.
You might get some ideas looking at that code, although I don't
remember if it every worked. Directly editing the document AST becomes
quite tricky if you go beyond simple paragraphs.
Lukas
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