Re: compilation error: "error: no matching function for call to 'String::String(String)'

Hello again,

Sorry to bother but I guess my C++ book isn't very good since it
obviously contains errors so the program code doesn't work with g++.

However I don't understand what the problem is. Last time the problem
was that "using namespace std" apparently had a "link" class/object
defined already. Now I get:

error: no matching function for call to 'String::String(String)'

See if you can spot the error because I can't:

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// memory-saving String class
// overloaded assignment and copy constructor
#include <iostream>
#include <cstring> //for strcpy(), etc.
using namespace std;
////////////////////////////////////////////////////////////////
class strCount //keep track of number
{ //of unique strings
private:
    int count; //number of instances
    char* str; //pointer to string
    friend class String; //make ourselves available
                                //member functions are private

//--------------------------------------------------------------
    strCount(char* s) //one-arg constructor
        {
        int length = strlen(s); //length of string argument
        str = new char[length+1]; //get memory for string
        strcpy(str, s); //copy argument to it
        count=1; //start count at 1
        }
    //--------------------------------------------------------------
    ~strCount() //destructor
        { delete[] str; } //delete the string
};
////////////////////////////////////////////////////////////////
class String //String class
{
private:
    strCount* psc; //pointer to strCount
public:
    String() //no-arg constructor
    { psc = new strCount("NULL"); }
    //--------------------------------------------------------------
    String(char* s) //1-arg constructor
    { psc = new strCount(s); }
    //--------------------------------------------------------------
    String(String& S) //copy constructor
    {
        psc = S.psc;
        (psc->count)++;
    }
    //--------------------------------------------------------------
    ~String() //destructor
    {
        if(psc->count==1) //if we are its last user,
            delete psc; // delete our strCount
        else // otherwise,
            (psc->count)--; // decrement its count
    }
    //--------------------------------------------------------------
    void display() //display the String
    {
        cout << psc->str; //print string
        cout << " (addr=" << psc << ")"; //print address
    }
    //--------------------------------------------------------------
    void operator = (String& S) //assign the string
    {
        if(psc->count==1) //if we are its last user,
            delete psc; // delete our strCount
        else // otherwise,
            (psc->count)--; // decrement its count
        psc = S.psc; //use argument's strCount
        (psc->count)++; //increment its count
    }
};
////////////////////////////////////////////////////////////////
int main()
{
    String s3 = "When the fox preaches, look to your geese.";
    cout << "\ns3="; s3.display(); //display s3

    String s1; //define String
    s1 = s3; //assign it another String
    cout << "\ns1="; s1.display(); //display it

    String s2(s3); //initialize with String
    cout << "\ns2="; s2.display(); //display it
    cout << endl;
    return 0;
}

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I didn't make the comments. I just copy/pasted the code so I don't
want to spend time on removing them as I also find it okay that
they're there.

Best regards / Med venlig hilsen
Martin JHrgensen

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