[antlr-interest] Grammar inheritance?

[Terence Parr]

On Oct 4, 2006, at 7:17 AM, Hill, Robert wrote:

> Does this work in 3.0b4?
> Im trying to create a base class using the grammar option  
> { superClass=baseGrammar; }

That is for specifying the Java class to drive from not the grammar.
> But for the derived grammar file its generating 'null.java' which  
> contains about 20 lines of code :(
>
> If it is working how do I create a subclass of a base grammer?

Currently there is no way.  A way to do so will appear in a future,  
just after the first real release.  There are a number of important  
players that want this and I have some good ideas about how to make  
it better than the mechanism in ANTLR 2. for example, I expect that  
the generated code for sub grammars will inherit not include rules  
from the super grammar.  This will significantly reduce code float  
found in the current version.  I would like to spend some time  
thinking about the  correct model before we jump.

Ter