>>>>> "Jim" == jweirich  <jweirich / one.net> writes:

    Jim> b[6] doesn't exist either.  Yet b[6,2] returns an empty string.

Oops ... I meant "empty list".   But of course you knew that :-)

-- 
-- Jim Weirich     jweirich / one.net    http://w3.one.net/~jweirich
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"Beware of bugs in the above code; I have only proved it correct, 
not tried it." -- Donald Knuth (in a memo to Peter van Emde Boas)