/*

 * Copyright 2011 Steven Gribble

 *

 *  This file is the solution to an exercise problem posed during

 *  one of the UW CSE 333 lectures (333exercises).

 *

 *  333exercises is free software: you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation, either version 3 of the License, or

 *  (at your option) any later version.

 *

 *  333exercises is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with 333exercises.  If not, see <http://www.gnu.org/licenses/>.

 */



// This implementation is taken from lec 11's exercise 2.



#ifndef _GETWORD_H_

#define _GETWORD_H_



#include <iostream>

#include <fstream>

#include <string>



using namespace std;



// A "GetWord" is a class that can be used to open a file and

// read successive white-space-separated, ASCII words from

// the file.

class GetWord {

 public:

  // Constructor.  Throws an exception on error.

  GetWord(string filename) : filename_(filename) {

    // We'll temporarily elevate the exceptions bitmask on

    // f_ so that an exception is thrown if we encounter an

    // error while opening filename.

    f_.exceptions(ifstream::failbit);



    // Try to open filename_.

    f_.open(filename_.c_str(), ifstream::in);



    // Clear the exceptions bitmask, so no more exceptions

    // are thrown.

    f_.exceptions(ifstream::goodbit);

  }



  // Destructor.

  ~GetWord() {

    if (f_.is_open())

      f_.close();

  }



  // Get the next word from the file.  Returns a non-empty

  // string if there is a next word, or an empty string

  // if we've hit EOF.

  string GetNextWord();



 private:

  // Disable the copy constructor and assignment operator.

  GetWord(const GetWord &gw);

  GetWord &operator=(const GetWord &gw);



  string filename_;

  ifstream f_;

};



#endif  // _GETWORD_H_