[antlr-interest] SYNTAX predicates in lexer

[Shalini Sharma]

---------- Forwarded message ----------
From: Shalini Sharma <shalini.sh at gmail.com>
Date: Mar 31, 2005 8:53 AM
Subject: SYNTAX predicates in lexer
To: "John B. Brodie" <jbb at acm.org>, 'antlr-interest' Interest
<antlr-interest at antlr.org>


header
{
# include<iostream>
using namespace std;
}
options {
       language="Cpp";

}
class testParser extends Parser;

c: A X
;

class testLexer extends Lexer;
options
{
k=2;
}

A:    (Z  "b")=> Z 'b' { cout<<"matched with B"<<endl;}
         |Z    {cout<<"matched without B"<<endl;}
        ;
X       :'x'
       ;
protected
Z:   ('a')*
       ;

when i give aaaaa  or aaaaaaaaab (wrong input ) parser hangs writing
"matched without B" . but on correct input it works fine .  i want it
to exit with some error .