[DotGNU]Treecc / Bison - List rule best pattern

[sergio]

Hi:

I hope not being of topic here.
I am currently changing a free Informix 4gl compiler that have code
generation in sematic actions of bison to use an AST. The parser is bison,
the lexer is C++ and all is built to be reentrant.

The main goal with this version is the cleaness, simplicity and
maintainabilty of the code.

I have choosed to use treecc because the code in bison and in .tc will
keep very clear and short.

In some rules, however i do not get a clear and short code.

I want to create a simple optional list (wich is one a very common rule in
the parser).

The tipicall bison code is:
  opt_function_list
    :
    | function_list
    ;

  function_list
    : abstract_function
    | function_list abstract_function
    ;

If i make the AST by hand tipically i create a vector in a class called
FunctionList and an AddFunction() method that pushes the new Function into
it.
In treecc i dont know how to do it.
Please someone tell me a simple (keep in mind that the goal is simplicity)
pattern to implement this in my parser ?

Thanks In Advance
Sérgio Ferreira