anchor.diff:  	;
   
   method_call_root
  -	: //primary
  -		primary_literal
  -		| ( class_qualifier | package_scope? ) hierarchical_identifier select_
  -		| empty_unpacked_array_concatenation
  -		| concatenation ( '[' range_expression ']' )?
  -		| multiple_concatenation ( '[' range_expression ']' )?
  -		| //function_subroutine_call
  -			tf_call
  -			| system_tf_call
  -			| method_call_root '.' method_call_body
  -			| ( 'std' '::' )? randomize_call
  -		| let_expression
  -		| '(' mintypmax_expression ')'
  -		//| cast
  -		| assignment_pattern_expression
  -		| streaming_concatenation
  -		| sequence_method_call
  -		| 'this'
  -		| '$'
  -		| 'null'
  +	: primary
   	| implicit_class_handle
   	;
   
  
positive.code: 	| empty_unpacked_array_concatenation
  	| concatenation ( '[' range_expression ']' )?
  	| multiple_concatenation ( '[' range_expression ']' )?
  	| function_subroutine_call
  	| let_expression
  	| '(' mintypmax_expression ')'
  	| //cast
  		( simple_type | constant_primary | signing | 'string' | 'const' ) '\'' '(' expression ')'
  	| assignment_pattern_expression
  	| streaming_concatenation
  	| sequence_method_call
  
negative.code: empty_unpacked_array_concatenation
  	: '{' '}'
  	;
  /*
  constant_function_call
  	: function_subroutine_call
  	;
  */
  tf_call
  	: ps_or_hierarchical_tf_identifier attribute_instance* ( '(' list_of_arguments ')' )?
  	;
  