Detecting a break in data

I am new to XML and XSL (but old to more conventional programming), and am
having trouble trying to find a way to compare the value of a field in one
record with the same field in the previous record (sorry - I suppose that
should be node).  Basically, I want to print all the records with a common
category in one block, then print some kind of separator, followed by all
the records of the next block (for 'print', what I mean is displaying
through a browser - ultimately I take a hard-copy, but I haven't started
looking into XSL-FO yet...) My XML source has a list of nodes at a given
level - I am looping through them using a for-each construct, but have now
realised that if I use a variable to store the value of one of the fields,
the variable is a) no longer available in the next iteration of the for-each
loop, and b) is not updatable to hold the 'new' current compare value.  I
suspect that I am approaching the problem from the wrong angle, given the
bias of too many tens of years coding for-next loops in various flavours,
and would welcome being steered in the right direction.

Many thanks,
Graham.

> Graham Smith (IPC 692)
> International Financial Systems
> Pfizer Limited
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