[antlr-interest] Older Grammar in ANTLR 3

[Pennington, Elliot]

Howdy All,

I've got an old grammar that used to work in ANTLR 2 but that now  
fails in ANTLR 3. I'd like to make the switch, but I'm at a loss as to  
how to fix this. For the following example code:

--------------

void input_a() {
    integer a, bb, xyz, b3, c, p, q;
    real b;
    a = b3;
    b = -2.5;
    xyz = 2 + a + bb + c - p / q;
    a = xyz * ( p + q );
    p = a - xyz - p;
}

-------------

I get this tree result:

-------------

def
	function_declaration
		type
  			void
		input_a
		(
		)
		code_block
			FailedPredicateException(code_block,{can't deal with predicates  
yet}?)
			FailedPredicateException(code_block,{synpred2_javalet}?)

------------

Here's the grammar I'm using. Has anyone seen anything like this  
before for a grammar that worked in ANTLR 2? I'm not sure how to get  
it to parse properly so I don't get the failed predicate exception.

Thanks,

Elliot

------------

grammar Javalet;
options {
	backtrack = true;
	output=AST;
	ASTLabelType=CommonTree;
	k=2;
	}
tokens	{
	FUNCTION = 'function';
}

@header {package javalet.compiler;}
@lexer::header{package javalet.compiler;}

def 	:	function_declaration
	;


code_block
	:	'{' statement* '}' -> (statement)*
	|	statement
	;

statement
	:	block_statement
	|	variable_declaration ';' -> variable_declaration
	|	assignment ';' -> assignment
	;

block_statement
	:	IF '(' value_0 ')' code_block
		(else_block)? -> ^(IF value_0 code_block (else_block)?)
	|	WHILE '(' value_0 ')' code_block -> ^(WHILE value_0 code_block)
	;

else_block
	:	ELSE code_block -> ^(ELSE code_block)
	;

assignment
	:	ID EQ value_0 -> ^(EQ ID value_0)
	;

variable_declaration
	:	type ID (',' ID)* -> ^(type ID*)
	;

function_declaration
	:	type ID '(' ')' code_block -> ^('function' type ID code_block)
	;

operator_0
	:	LOGICAL_OR
	;
	
LOGICAL_OR
	:	'||'
	;

operator_1
	:	LOGICAL_AND
	;

LOGICAL_AND
	:	'&&'
	;

operator_2
	:	LOGICAL_EQUALITY
	|	LOGICAL_INEQUALITY
	|	LOGICAL_GREATER_THAN
	|	LOGICAL_LESS_THAN
	|	LOGICAL_GREATER_THAN_OR_EQUAL
	|	LOGICAL_LESS_THAN_OR_EQUAL
	;

LOGICAL_EQUALITY
	:	'=='
	;

LOGICAL_INEQUALITY
	:	'!='
	;

LOGICAL_GREATER_THAN
	:	'>'
	;

LOGICAL_LESS_THAN
	:	'<'
	;

LOGICAL_GREATER_THAN_OR_EQUAL
	:	'>='
	;

LOGICAL_LESS_THAN_OR_EQUAL
	:	'<='
	;

operator_3
	:	ADD
	|	SUBTRACT
	;

ADD	:	'+';
SUBTRACT:	'-';

operator_4
	:	MULTIPLY
	|	DIVIDE
	;

MULTIPLY:	'*';
DIVIDE	:	'/';

value_0
	:	value_1 operator_0 value_0 -> ^(operator_0 value_1 value_0)
	|	value_1
	;

value_1
	:	value_2 operator_1 value_1 -> ^(operator_1 value_2 value_1)
	|	value_2
	;

value_2
	:	value_3 operator_2 value_2 -> ^(operator_2 value_3 value_2)
	|	value_3
	;

value_3
	:	value_4 operator_3 value_3 -> ^(operator_3 value_4 value_3)
	|	value_4
	;

value_4
	:	value_5 operator_4 value_4 -> ^(operator_4 value_5 value_4)
	|	value_5
	;

value_5
	:	'(' value_0 ')' -> ^(value_0)
	|	num
	;


num
	:	(REAL|INTEGER|ID)
	;

WS	:	(' '|'\r'|'\t'|'\u000C'|'\n') {$channel=HIDDEN;}
	;

COMMENT	:	'/*' .* '*/' {$channel=HIDDEN;}
  	;

LINE_COMMENT
	:	'//' ~('\n'|'\r')* '\r'? '\n' {$channel=HIDDEN;} ;

//fragment
IF	:	'if' ;

//fragment
ELSE	:	'else' ;

//fragment
WHILE	:	'while' ;


//fragment
DO	:	'do' ;

//fragment
FOR	:	'for' ;

//fragment
EQ	:	'='
	;

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

fragment
LETTER	:	('a'..'z'|'A'..'Z') ;

type	:	TYPE_VOID
	|	TYPE_INTEGER
	|	TYPE_REAL
	;
	
TYPE_VOID
	:	'void'
	;
TYPE_INTEGER
	:	'integer'
	;
TYPE_REAL
	:	'real'
	;

INTEGER	:	(DIGIT)+ ;

REAL	:	('+'|'-') (DIGIT)+ '.' (DIGIT)+ ;

ID	:	LETTER ('_' | DIGIT | LETTER)* ;

____________

elliot at wpi.edu
Worcester Polytechnic Institute '09
Computer Science