test="$seq1 = $seq2"

is true just if some item in the first sequence equals some item in teh
second.

select="for $r in $roles return string($r/@ROLE)"

which could more easily be written as

select="$r/string(@ROLE)"



> if (index-of($roles, $r)) then true() else false()

if (anything) then true() else false() 
is always the same as
boolean(anything)


David




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