anchor.diff:  		(
   			DOT (NEWLINE)*
   			e=member_reference_expression[e]
  +			(NULLABLE_SUFFIX {
  +					ue = new UnaryExpression(e.LexicalInfo);
  +					ue.Operator = UnaryOperatorType.SafeAccess;
  +					ue.Operand = e;
  +					e = ue;
  +				}
  +			)?
   		)
   		|
   		(
  
positive.code: 					)*
  				)?
  			RPAREN
  			(
  				(
  					(hash_literal_test)=>initializer=hash_literal
  
negative.code: 				slice[se] (COMMA slice[se])*
  			)
  			RBRACK
  			(NULLABLE_SUFFIX {
  					ue = new UnaryExpression(e.LexicalInfo);
  					ue.Operator = UnaryOperatorType.SafeAccess;
  					ue.Operand = e;
  					e = ue;
  				}
  			)?
  		)
  		|
  		(
  