DFA

Just a quick question. When I used flex a while back, I defined a
floating point number or integer as:


number [0-9]
exp [Ee][+-]?{number}+
numtype {number}*\.?{number}+{exp}?


While flipping through the 2nd edition of Lex and Yacc, they use the
following definition:


number [0-9]
exp [Ee][+-]?{number}+
numtype ({number}+|{number}*\.{number}+)({exp})?


Is there any advantage in using the Lex and Yacc definition? Does it use
fewer DFA states?
[I don't see any compelling advantage either way, except that the first
example works differently (worse) in AT&T lex because there's no parens
around the {exp}. We did it the way we did because we wanted an example
for the | operator and parenthesised patterns. Note that neither version
accepts "123." which I'd call a bug. -John]
--

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