polymorphism by dynamic binding

im working on a toy hierarchy but im getting a linkage error
error LNK2019: unresolved external symbol "public: __thiscall StuffedToy::StuffedToy(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,double)" (??0StuffedToy@@QAE@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@0N@Z) referenced in function _main

fatal error LNK1120: 1 unresolved externals

i dont know why im getting this can anyone help?

Code:

---

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

class Toy{
public:
        Toy(const string &,double=0.0);
        void setName(const string &);
        string getName()const;
        void setID(double);
        double getID()const;

        virtual void print() const;

};
class StuffedToy : public Toy{
public:
        StuffedToy(const string&,const string&,double=0.0);
        void setColor(const string &);
        string getColor()const;

        virtual void print() const;

};

int main(){

        StuffedToy stuffedToy("bear","brown",123);
        StuffedToy *stuffedToyPtr = 0;

                stuffedToyPtr = &stuffedToy;
        cout<<"dynamic binding: ";
        stuffedToyPtr->print();

        cout<<endl;

        return 0;
}

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It looks like you forgot to implement the functions in your excitement :)

Quote:

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Originally Posted by laserlight

It looks like you forgot to implement the functions in your excitement :)

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not quite sure what you mean by that

Quote:

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Originally Posted by ptg

not quite sure what you mean by that

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He means this:

Code:

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void Foo();

int main()
{
    Foo(); //The compiler's happy, but the linker's not.
}

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You can't possibly expect that to link. The same applies to the snippet in your OP.

Quote:

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Originally Posted by Plasmator

He means this:
You can't possibly expect that to link. The same applies to the snippet in your OP.

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so i have to make the functions after the main
like
void Toy::setName(const string& name)
{
toyname=name;
}

Quote:

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so i have to make the functions after the main

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Yes, or implement them inline with the class definition, but what you want to do is typically better for separation into a header and a source file.

Quote:

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Originally Posted by laserlight

Yes, or implement them inline with the class definition, but what you want to do is typically better for separation into a header and a source file.

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whats implementing them inline with the class definition mean

Quote:

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whats implementing them inline with the class definition mean

---

Code:

---

class Toy{
public:
    // ...
    void setName(const string& name)
    {
        toyname=name;
    }
    // ...
};

---

Put simply: The compiler only needs to know, "What do I do?". Your code answers this well enough.

But the linker needs to also know, "How do I do that?". Your code doesn't answer this question.

well i figured it out now. took me a while to get it but i finally got it to work