original_string: public function delete_index(string $table, string $key): bool
    {
      return $this->language->delete_index($table, $key);
    }
code: public function delete_index(string $table, string $key): bool
    {
      return $this->language->delete_index($table, $key);
    }
code_tokens: public function delete_index ( string $ table , string $ key ) : bool { return $ this -> language -> delete_index ( $ table , $ key ) ; }
docstring: Deletes index on a column of the table.
  
  @todo far vedere a thomas perchè non funziona/return data
  
  ```php
  \bbn\x::dump($db->delete_db_index('table_users','id_group'));
  // (void)
  ```
  
  @param string $table The table's name.
  @param string $key The key's name.
  @return bool
docstring_tokens: Deletes index on a column of the table .