D Parsing (again)/ D grammar

[Vladimir Kazanov via Digitalmars-d]

On Thursday, 2 October 2014 at 18:20:36 UTC, Philippe Sigaud via 
Digitalmars-d wrote:
> I did that during this summer, almost to the point it was
> self-sustained (that is, the GLL parser generator was used to 
> generate
> a parser for grammars files). I chose a range interface: input 
> is a
> string, the parse forest is output as a range of parse trees.

Nice! Is it public? Github?

> Halas, even with some shortcuts on Kleene stars it was quite 
> slow. I
> tried to use threads (spawning worker threads on alternatives), 
> but
> that did not change the timings much.

AFAIK, multithreading is a bad idea in parsing.

Actually, in the gll-combinators Scala project they have similar 
speed problems. I don't if it's a fundamental algorithm problem 
or an implementation details that lead to slowdowns.