worditer.h

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#ifndef _WORDSTREAMITERATOR_H
#define _WORDSTREAMITERATOR_H

// Owen Astrachan 7/3/95, modified 4/9/99
//
// class WordStreamIterator
//
// void Open(string name)
//        -- initializes iterator to file specified by name
//
// void Init(), void Next(), bool HasMore()
//        -- "standard" iterating functions (see below)
//
// usage: call Init(), before accessing Current()
//        call Next() to move to  the next word in the stream
//        call Current() to access the current word
//        call HasMore() to determine if Current() is valid
//
// string Current()
//        -- returns current string (see below)
//
// WordStreamIterator iter;
// iter.Open("testfile.dat");
// for(iter.Init(); iter.HasMore(); iter.Next())
//    cout << iter.Current() << endl;
//
//

#include <string>
#include <fstream>
using namespace std;

class WordStreamIterator
{
  public:
    WordStreamIterator();
    void Open(const string & name);   // bind stream to specific text file
    void Init();                      // initialize iterator
    string Current();                 // returns current word
    bool HasMore();                   // true if more words
    void Next();                      // advance to next word

  private:
    string myWord;                    // the current word
    bool myMore;                      // true if more words
    ifstream myInput;                 // the stream to read from
};

#endif