anchor.diff:  empty_unpacked_array_concatenation
   	: '{' '}'
   	;
  -
  +/*
   constant_function_call
   	: function_subroutine_call
   	;
  -
  +*/
   tf_call
   	: ps_or_hierarchical_tf_identifier attribute_instance* ( '(' list_of_arguments ')' )?
   	;
  
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: 	;
  
  method_call_root
  	: primary
  	| implicit_class_handle
  	;
  
  