Let's stop parser Hell

[Roman D. Boiko]

On Saturday, 7 July 2012 at 20:04:21 UTC, Andrei Alexandrescu 
wrote:
> Doesn't ANTLR use full-fledged character-level LL(*) parsing 
> even in the tokenizer?

Since I didn't understand your question I assume that my 
statement was somehow incorrect (likely because I made some wrong 
assumptions about ANTLR). I didn't know about its existence until 
today and still don't understand it completely. What I think I 
understood is that it uses DFA for deciding which grammar rule to 
apply instead of doing backtracking. I also think that it uses 
DFA for low-level scanning (I'm not sure).

The idea to introduce DFA for both determining which rule to 
apply and lexing of terminal symbols appeared to me much earlier, 
and the suggestion to introduce them into Pegged is one of 
options which I think could extremely improve performance.