wordcount.c

C++ PRIME书中的原代码,看本书时可以学习的例子.

#include "WordCount.h"

ostream& operator <<( ostream& os, const Location& lc ) 
{ 
    // output of a Loc object:  < 10,37 >
    os << "<" << lc._line 
       << "," << lc._col << "> ";

    return os;
}

ostream& 
operator <<( ostream& os, const WordCount& wd ) 
{
    os << "<" << wd._occurList.size() << "> " 
       << wd._word << endl;

    int cnt = 0, onLine = 6;
    vector<Location>::const_iterator first = wd._occurList.begin();
    vector<Location>::const_iterator last  = wd._occurList.end();

    for ( ; first != last; ++first ) 
    { 
	// os << Location
	os << *first << " ";

	// formatting: 6 to a line
	if ( ++cnt >= onLine )
	   { os << "\n"; cnt = 0;  }

    }
    return os;
}

istream& 
operator >>( istream &is, WordCount &wd ) 
{
/* format of WordCount object to be read:
 * <2> string
 * <7,3> <12,36> 
 */

    int ch;

    /* read in less-than token. if not present
     * place istream in bad state and exit
     */
    if ((ch = is.get()) != '<' ) 
    {
        // is.setstate( ios_base::badbit );
        return is;
    }

    // read in size value. 
    int occurs;
    is >> occurs;

    // grab >; not checking for error
    while ( is && (ch = is.get()) != '>' ) ;

    is >> wd._word;

    // read in the locations;
    // format of each location: < line, col >
    for ( int ix = 0; ix < occurs; ++ix ) 
    {
        int line, col;

        // extract values
        while (is && (ch = is.get())!= '<' ) ;
        is >> line; 

        while (is && (ch = is.get())!= ',' ) ;
        is >> col; 

        while (is && (ch = is.get())!= '>' ) ;

        wd._occurList.push_back( Location( line, col ));
    }
    return is;
}