find matching contiguous text

[bruce]

Hi.

I have a xpath test that generates the text/html between two xpath
functions, basically a chunk of HTML between two dom elements.

However, it's slow. As a test, I'd like to compare the speed if I get
all the HTML following a given element, and then get all the HTML
preceding a given element.. and then do a "union/join/intersection" of
the text between the two text segments.

I'm trying to find an efficient/effective approach to determining the
contiguous matching text, where the text starts with the 1st line in
the test from the following element test.

Thanks