anchor.diff:     ;
   
   block_reg_declaration
  -   : 'reg' ('signed')? (range)? list_of_block_variable_identifiers ';'
  +   : 'reg' ('signed')? (range_)? list_of_block_variable_identifiers ';'
      ;
   
   list_of_block_variable_identifiers
  
positive.code:    : '[' dimension_constant_expression ':' dimension_constant_expression ']'
     ;
  
  range
     : '[' msb_constant_expression ':' lsb_constant_expression ']'
     ;
  
  
negative.code:    ;
  
  specparam_declaration
     : 'specparam' (range_)? list_of_specparam_assignments ';'
     ;
  
  // 2.1.2 Port declarations
  inout_declaration
     : 'inout' (net_type)? ('signed')? (range_)? list_of_port_identifiers
     ;
  
  input_declaration
     : 'input' (net_type)? ('signed')? (range_)? list_of_port_identifiers
     ;
  
  output_declaration
     : 'output' (net_type)? ('signed')? (range_)? list_of_port_identifiers
     | 'output' ('reg')? ('signed')? (range_)? list_of_port_identifiers
     | 'output' 'reg' ('signed')? (range_)? list_of_variable_port_identifiers
     | 'output' (output_variable_type)? list_of_port_identifiers
     | 'output' output_variable_type list_of_variable_port_identifiers
     ;
  