[sword-devel] Comming soon: new improved sword searching

Matthew Donadio sword-devel@crosswire.org
Mon, 09 Sep 2002 12:27:18 -0400

Lamar Owen wrote:
> Of course, if the existing one is DFA, and the replacement is NFA,
> then some regexes may break in subtle ways.... See the O'Reilly regex book
> for details on how deterministic finite automatons and non-deterministic
> finite automatons differ from the point of view of crafting regexes.

Can you elaborate on this?  I know the theory behind this, and am a bit
confused by the statment.  It is pretty straightforward to convert a DFA
into an RE.  The textbook method for converting an RE into a DFA is RE
-> NFA+e moves -> NFA -> DFA.  You then can perform minimization of the
DFA to get the optimum one.

Matthew Donadio (m.p.donadio@ieee.org)