[antlr-interest] Resolving ambiguity

[Stefan]

Hello!

What is the approach to resolve semantical ambiguity in grammar in 
ANTLRv3? Consider the grammar:

grammar My;

fragment
DIGIT   :   '0'..'9';

fragment
NONDIGIT:   'a'..'z' | 'A'..'Z' | '_';

IDENTIFIER
     :   NONDIGIT (DIGIT | NONDIGIT)*;

function_definition
     :   'function' IDENTIFIER;

function_call
     :   IDENTIFIER;

variable_definition
     :   'var' IDENTIFIER;

expression
     :   IDENTIFIER;

statement
     :
     (
         function_definition
         | function_call
         | variable_definition
         | expression
     ) ';';

program :   statement+;

For input "something;" I want to select the appropriate rule depending 
on the meaning of "something" - if it's a function or variable. How do I 
do that?


Stefan Chrobot