[antlr-interest] Re: When does AST construction go through factory?

[Daniel Gackle]

Ter,

You beat me to the punch, I was just playing with antlr-2.7.2rc2 to see if
it changed the behavior.  Indeed it does!  But now I'm seeing two new
problems.  Perhaps they have to do with a version mismatch between RC2 and
the C# codegen? (The latest C# version if I am not mistaken is 2.7.2a4?)

My previous example was something like this (where IDENT is a lexer token
and MYTOKEN is not):

tokens {
 IDENT<AST=MyIdentifierNode>;
 MYTOKEN<AST=MyASTNode>;
}

(Problem 1) For IDENT, the parser does:

astFactory.create(LT(1), "MyIdentifierNode");

which is wonderful in that it is a call to the factory, but it fails to
compile against the C# runtime with an error that says "cannot convert Token
to int".

(Problem 2) For MYTOKEN, I don't see any generated code that maps to
MyASTNode.  The parser used to do this:

astFactory.registerFactory(MYTOKEN, "MyASTNode");

But that's gone, and I can't find anything in the generated code that
replaces it.  As a result, when the AST for MYTOKEN gets created, its type
is not MyASTNode but simply the default AST type.

Would anyone (Micheal? :) care to comment?  Based on a brief look at the
improved ASTFactory class, there appear to be methods I can call to set up
the mappings in my own code, and bypass the Tokens section altogether.  Does
that sound like a valid workaround for now?

Thanks,
Daniel

--- In antlr-interest at yahoogroups.com, Terence Parr <parrt at j...> wrote:
> Hi.  ANTLR 2.7.2 should be out tomorrow or over the weekend.  It fixes
> this so that all AST creation goes thru the factory. :)
>
> Ter
>


 

Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/