anchor.diff:  in_stmt	: column[null] keyIN LPAREN qstring_list RPAREN;
   
   cond_expr
  -	: cond_term
  -	| cond_expr keyOR cond_term;
  +	: cond_term (keyOR cond_expr)?
  +	//| cond_expr keyOR cond_term
  +	;
   
   cond_term
  -	: cond_factor
  -	| cond_term keyAND cond_factor;
  +	: cond_factor (keyAND cond_term)?
  +	//| cond_term keyAND cond_factor
  +	;
   	
   cond_factor
  -	: (keyNOT)? conditional_primary;
  -
  -conditional_primary
  -	: simple_cond_expr | LPAREN cond_expr RPAREN;
  +	: (keyNOT)? cond_primary;
  +
  +cond_primary
  +	: simple_cond_expr 
  +	| LPAREN cond_expr RPAREN
  +	;
   
   simple_cond_expr
  -	: comparison_expr
  +	: comp_expr
   	| between_expr
   	| like_expr
   	| in_expression
   	| null_comparison_expr
  -	| empty_collection_comparison_expr
  +	| empty_collection_comp_expr
   	| collection_member_expr
   	;
   
  
positive.code: 	;
  
  simple_arithmetic_expr
  	: arithmetic_term
  	| simple_arithmetic_expr ( '+' | '-' ) arithmetic_term;
  
  arithmetic_term
  	: arithmetic_factor
  	| arithmetic_term ( '*' | '/' ) arithmetic_factor;
  
  arithmetic_factor
  	: ( '+' | '-' )? arithmetic_primary;
  
negative.code: 
  single_valued_path_expression
  	: state_field_path_expr 
  	| single_valued_association_path_expr
  	;
  
  state_field_path_expr
  	: (identification_var | single_valued_association_path_expr) DOT state_field
  	;
  
  single_valued_association_path_expr
  	: identification_var DOT (single_valued_association_field DOT)* single_valued_association_field;
  
  collection_valued_path_expression
  	: identification_var DOT (single_valued_association_field DOT)* collection_valued_association_field;
  
  state_field
  	: (embedded_class_state_field=ID DOT)* simple_state_field=ID;
  
  collection_valued_association_field
  	: ID;
  	
  single_valued_association_field
  	: ID;
  	
  identification_var
  	: ID;
  	
  boolean_literal
  