Official D Grammar

[Tobias Pankrath]

On Thursday, 2 May 2013 at 17:13:46 UTC, Russel Winder wrote:
> On Thu, 2013-05-02 at 17:44 +0100, Bruno Medeiros wrote:
> […]
>> To be honest, that's one of the reasons that put me off 
>> working with ANLTR. It seems easy to create a parser with 
>> ANTLR, but to create an efficient, well-behaved parser it 
>> looks quite complicated, in the sense that you can't abstract 
>> yourself from what is happening under the hood... you have to 
>> read a lot of theory and documention to learn the innards of 
>> ANTLR, and understand what kind of code it's actually 
>> generating, and how it processes input. (at moments it feels 
>> like you have to take a degree to learn how to use it 
>> effectively...)
>
> The Groovy parser is an ANTLR 2.7.7 grammar, it works well and 
> quickly.
> I think the trick is to work with the LL(k) idioms and avoid 
> letting
> LALR(1) thoughts creep in.

LALR(1) is O(n) last time I looked. Both Ll(k) and LALR(k) should 
never backtrack. Dunno what Antlr is doing.