Why does ANTLR not analyze the entire input?

Question

I'm new to ANTLR, so this is probably a simple question.
I defined a simple grammar, which should include arithmetic expressions with numbers and identifiers (lines starting with a letter and continuing with one or more letters or numbers).

The grammar is as follows:

grammar while;

@lexer::header {
  package ConFreeG;
}  

@header {
  package ConFreeG;

  import ConFreeG.IR.*;
}

@parser::members {
}

arith:
    term
    | '(' arith ( '-' | '+' | '*' ) arith ')'  
    ;

term  returns [AExpr a]:    
    NUM
    {
        int n = Integer.parseInt($NUM.text);
        a = new Num(n);
    }
    | IDENT
    {
        a = new Var($IDENT.text);
    }
    ;

fragment LOWER : ('a'..'z');
fragment UPPER : ('A'..'Z');
fragment NONNULL : ('1'..'9');
fragment NUMBER : ('0' | NONNULL);
IDENT  : ( LOWER | UPPER ) ( LOWER | UPPER | NUMBER )*;
NUM    : '0' | NONNULL NUMBER*;

fragment NEWLINE:'\r'? '\n';
WHITESPACE  :   ( ' ' | '\t' | NEWLINE )+ { $channel=HIDDEN; };

I am using ANTLR v3 with the ANTLR IDE Eclipse plugin. When I parse an expression (8 + a45)with an interpreter, only part of the parse tree is generated:

Why is the second term (a45) not analyzed? The same thing happens if both conditions are numbers.

Thank,

Martin Vibo

Answer 1

, EOF ( ), .

:

parse
  :  arith EOF
  ;

arith: