original_string: public function begin()
      {
          $this->current = $this->current instanceof Transaction
              ? $this->current->newTransaction()
              : new Transaction;
      }
code: public function begin()
      {
          $this->current = $this->current instanceof Transaction
              ? $this->current->newTransaction()
              : new Transaction;
      }
code_tokens: public function begin ( ) { $ this -> current = $ this -> current instanceof Transaction ? $ this -> current -> newTransaction ( ) : new Transaction ; }
docstring: Should be called after transaction started.
  
  @return void
docstring_tokens: Should be called after transaction started .