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POC++ Templates and Classes
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  1. POC++ Templates and Classes
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    copied!<p>I would like to sort different types of numbers in different files as a learning exercise. I've managed to get doubles and ints to sort correctly, but cannot get my own type (to sort a deck of cards) to format correctly. I've managed to get it narrowed down to my <strong>sort function in the Reader Class</strong>. I'm getting all sorts of errors. What exactly am I doing wrong? Or am I missing something? Thanks everyone, I hope I explained my problems clearly.</p> <p>My file I created for Cards looks something like... </p> <pre><code>1 11 (meaning Jack of Diamonds) 2 8 (meaning 8 of hearts) </code></pre> <p>etc...</p> <p>errors: </p> <blockquote> <p>error: no match for 'operator&lt;' in '((Reader<em>)this)->Reader::array[compareIndex] &lt; ((Reader</em>)this)->Reader::array[smallestIndex]'</p> <p>error: cannot convert 'Card' to 'int' in initialization</p> <p>error: no match for 'operator=' in '((Reader*)this)->Reader::array[smallestIndex] = temp'</p> </blockquote> <p><strong>My Code</strong></p> <p>Lastly, Main</p> <pre><code>#include &lt;iostream&gt; #include "Reader.h" #include "Card.h" using namespace std; int main() { Reader&lt;int&gt; nums; Reader&lt;double&gt; dubs; Reader&lt;Card&gt; cards; int number; do { cout &lt;&lt; "Enter 1 if your file contains integers\n" &lt;&lt; "Enter 2 if your file contains doubles\n" &lt;&lt; "Enter 3 if your file contains Cards:\n" &lt;&lt; "Enter a number: "; cin &gt;&gt; number; if (number == 1){ nums.open_IO(); nums.read_array(); nums.sort(); nums.write_array(); nums.close_IO(); } else if (number == 2){ dubs.open_IO(); dubs.read_array(); dubs.sort(); dubs.write_array(); dubs.close_IO(); } else if (number == 3){ cards.open_IO(); cards.read_array(); cards.sort(); cards.write_array(); cards.close_IO(); } } while ((number != 1) &amp;&amp; (number != 2) &amp;&amp; (number != 3)); } </code></pre> <p>Reader.h</p> <pre><code>#ifndef READER_H #define READER_H #include &lt;string&gt; #include &lt;fstream&gt; using namespace std; template &lt;class rList&gt; class Reader { public: static const int SIZE = 50; Reader(); bool open_IO(); void close_IO(); bool read_array(); bool write_array(); void sort(); private: // Ask for the files void ask_filenames(); rList array[SIZE]; int readSize; // input file names and stream to get the data string readFileName; ifstream inFile; // output file names and stream to get the data string writeFileName; ofstream outFile; bool askedFileNames; }; #endif #include "Reader.cpp" </code></pre> <p>My Reader.Cpp file</p> <pre><code>// File: Reader.cpp #ifndef READER_CPP #define READER_CPP #include "Reader.h" #include &lt;iostream&gt; using namespace std; /*************************************************************************** * Contructors and modifying functions defined in "Reader.h" ***************************************************************************/ template &lt;class rList&gt; Reader&lt;rList&gt;::Reader() { askedFileNames = false; readFileName = ""; writeFileName = ""; readSize = 0; rList empty; for( int i = 0; i&lt;SIZE; i++ ) array[i]=empty; } template &lt;class rList&gt; bool Reader&lt;rList&gt;::open_IO(){ if(!askedFileNames) ask_filenames(); inFile.open(readFileName.c_str()); //we can't pass a string, we need a char array if(!inFile.is_open()) { return false; } outFile.open(writeFileName.c_str()); if(!outFile.is_open()) { inFile.close(); //inFile opened successfully so it needs to be closed now return false; } return true; } template &lt;class rList&gt; void Reader&lt;rList&gt;::close_IO() { inFile.close(); outFile.close(); } template &lt;class rList&gt; bool Reader&lt;rList&gt;::read_array() { if(inFile.is_open()) { inFile &gt;&gt; readSize; int index = 0; while(!inFile.eof() &amp;&amp; index &lt; readSize) { inFile &gt;&gt; array[index++]; //increments index after assigning value } readSize = index; //the input file could have had fewer numbers so set readSize return true; } return false; } template &lt;class rList&gt; bool Reader&lt;rList&gt;::write_array() { if(outFile.is_open()) { outFile &lt;&lt; readSize &lt;&lt; endl; //don't forget the number indicating the element co int index = 0; while(index &lt; readSize) { outFile &lt;&lt; array[index++] &lt;&lt; endl; } return true; } return false; } template &lt;class rList&gt; void Reader&lt;rList&gt;::sort() { int startIndex = 0; int compareIndex; int smallestIndex; bool smallerFound; while(startIndex &lt; readSize) { smallestIndex = startIndex; compareIndex = startIndex + 1; smallerFound = false; while(compareIndex &lt; readSize) { //find the smallest value from the starting index if(array[compareIndex] &lt; array[smallestIndex]) { smallestIndex = compareIndex; smallerFound = true; } compareIndex++; } if(smallerFound) { //only swap the values if a smaller value is found int temp = array[startIndex]; array[startIndex] = array[smallestIndex]; array[smallestIndex] = temp; } startIndex++; } } /*-------------------------------------------------------------- This function asks the user for the filenames. This operation is placed in a separate function because it is called multiple times. --------------------------------------------------------------*/ template &lt;class rList&gt; void Reader&lt;rList&gt;::ask_filenames() { cout &lt;&lt; "Welcome. Please type in the name of the file to read the numbers.\n"; cin &gt;&gt; readFileName; cout &lt;&lt; "Thank you. Please type in the name of the file to write the numbers.\n"; cin &gt;&gt; writeFileName; askedFileNames = true; } #endif </code></pre> <p>Card.h</p> <pre><code>#include &lt;ostream&gt; #include &lt;string&gt; #include "Reader.h" using namespace std; class Card{ public: static const int SIZE = 50; enum SUIT {clubs, diams, hears, spads }; enum RANK {ace=1, two, thr, fou, fiv, six, sev, eig, nin, ten, jac, que, kin}; Card(); Card(int newSuit, int newRank); void change(int newSuit, int newRank); friend ostream&amp; operator &lt;&lt; ( ostream&amp; out, Card theCard ); friend istream&amp; operator &gt;&gt; ( istream&amp; in, Card theCard ); private: void change_rank(int newRank); void change_suit(int newSuit); string get_rank() const; string get_suit() const; SUIT suit; RANK rank; }; </code></pre> <p>Card.cpp</p> <pre><code> #include &lt;iostream&gt; #include &lt;string&gt; #include "Card.h" using namespace std; Card::Card() { suit = spads; rank = ace; } Card::Card(int newSuit, int newRank) { change(newSuit, newRank); } void Card::change( int newSuit, int newRank ) { change_suit( newSuit ); change_rank( newRank ); } ostream&amp; operator &lt;&lt; ( ostream&amp; out, Card theCard ) { out &lt;&lt; theCard.get_rank() &lt;&lt; " of " &lt;&lt; theCard.get_suit(); return out; } istream&amp; operator &gt;&gt; ( istream&amp; in, Card theCard ) { int aSuit; int aRank; in &gt;&gt; aSuit &gt;&gt; aRank; return in; } // private member functions to set the private variables with their // corresponding values: integer input -&gt; enumerated type; void Card::change_rank( int newRank ) { if( newRank == ace ) rank = ace; else if( newRank == two ) rank = two; else if( newRank == thr ) rank = thr; else if( newRank == fou ) rank = fou; else if( newRank == fiv ) rank = fiv; else if( newRank == six ) rank = six; else if( newRank == sev ) rank = sev; else if( newRank == eig ) rank = eig; else if( newRank == nin ) rank = nin; else if( newRank == ten ) rank = ten; else if( newRank == jac ) rank = jac; else if( newRank == que ) rank = que; else if( newRank == kin ) rank = kin; } void Card::change_suit( int newSuit ) { if( newSuit == clubs ) suit = clubs; else if( newSuit == spads ) suit = spads; else if( newSuit == diams ) suit = diams; else if( newSuit == hears ) suit = hears; } // Private member functions to extract the information from the card // class. string Card::get_rank() const { if( rank == ace ) return "ace"; if( rank == two ) return "two"; if( rank == thr ) return "three"; if( rank == fou ) return "four"; if( rank == fiv ) return "five"; if( rank == six ) return "six"; if( rank == sev ) return "seven"; if( rank == eig ) return "eight"; if( rank == nin ) return "nine"; if( rank == ten ) return "ten"; if( rank == jac ) return "jack"; if( rank == que ) return "queen"; if( rank == kin ) return "king"; return "get_rank: error"; } string Card::get_suit() const { if( suit == diams ) return "D"; if( suit == hears ) return "H"; if( suit == spads ) return "S"; if( suit == clubs ) return "C"; return "get_suit: error"; } </code></pre>
 

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