[antlr-interest] State Machines Galore

Terence Parr parrt at cs.usfca.edu
Sat Jan 7 12:28:33 PST 2006


On Jan 7, 2006, at 12:23 PM, Jeff Barnes wrote:

>> Actually, v3 builds something more complicated.  For
>> your
>> entertainment, run
>>
>> java org.antlr.Tool -dfa -nfa t.g
>
> Thanks, Terence, for the glimpse into ANTLR 3's
> machine. It is, indeed, more complicated. In fact,
> most humans could safely regard the extra epsilon
> transitions as superfluous. What significance do they
> have for ANTLR?
>
> Thanks again for the knowledge.

My pleasure.  It turns out I need extra epsilon's to aid in NFA->DFA  
conversion.  I need a state that begins an alternative that does not  
have a downward link to the next alternative :)

Ter


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