Help with elisp

["David Chadd" <d.chadd@uea.ac.uk>]

Apologies for a question demonstrating beginner's total Elisp
incompetence.  I want to make lists out of series of
attribute-values in an xml file.  (The values are sigla of
manuscripts.)  These are e.g. in the form:

  wit="CAO-C Alb2 Hyd" 

Having found the string of values (CAO-C Alb2 Hyd) with a regexp
search, I simple-mindedly thought I would be able to do something like

  (setq wits (split-string (match-string 1)))

This does indeed make a list --- (listp wits) returns T --- but the
lists don't behave as I would expect.  For instance, they don't
respond correctly to (set-difference), (intersection) etc.  And for
reasons I can guess at, but don't know enough to do anything about,
the lists are in the form ("CAO-C" "Alb2" "Hyd") rather than (CAO-C
Alb2 Hyd).

I'm obviously going totally the wrong way about this.  How should I be
trying to make a conventional Lisp list out of a found string of this
kind?  Advice and guidance gratefully received.

DC
-- 
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Professor David Chadd
University of East Anglia
Norwich NR4 7TJ, UK
net: <d.chadd@uea.ac.uk>
fax: +44 (0)1263 250454
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