[antlr-interest] lookahead DFA too big?

[Terence Parr]

The problem is that the DFA it creates is just too doggone big.  
Coincidentally, I have a graduate student who plans on working on DFA  
minimization; of course that won't help if the NFA to DFA conversion  
times out because the minimization comes afterwards. If you get to the  
code generation phase, however, the DFA minimization should help.

Sorry I don't have a good answer for you right now. One thing that you  
might try is separating the lexer into multiple pieces and then using  
an import grammar statement. This forces the lexer to be broken up  
into multiple DFA I believe, one per included lexer.
Ter

On Mar 6, 2009, at 11:38 AM, Andreas Meyer wrote:

> Terence Parr schrieb:
>> Hi Andreas, I'm neck deep in another problem at the moment. Can you
>> try increasing the timeout?
>>
>>  -Xconversiontimeout t  set NFA conversion timeout for each decision
>>
>> try 100000 or something liek that.
>
> Yes, I already did that. Sorry if my initial mail two days back was  
> too
> verbose, probably you did not see it :-) The result of running ANTLR  
> was
> a huge java file, with lots of definitions for follow-sets (many
> thousands) and dfa-transitions. The follow-sets issue I resolved  
> with a
> perl script (by moving them into a set of static initializer  
> functions),
> but the dfa-transitions look a little tricky to move around with perl,
> so javac still cannot compile the parser.
>
> If you think it's feasible to change the corresponding string  
> templates
> for a string template newbie (me), I would really appreciate if you
> could tell me which parts I need to take care of.
>
>
> Thanks a lot!
> Andreas Meyer
>
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