I have come across some C++ code.Why we have to use *this in block instead of this?

Question

I have the following code, and I'm wondering why it uses *this instead of this.

class Quotation
{
protected:
    int value;
    char* type;
public:
    virtual Quotation* clone()=0;

    char * getType()
    {
        return type;
    }

    int getValue()
    {
        return value;
    }
};


class bikeQuotation : public Quotation
{
public:
    bikeQuotation(int number)
    {
        value=number;
        type="BIKE";
    }

    Quotation * clone()
    {
        return new bikeQuotation(*this);  // <-- Here!
    }
};

Because `this` is a pointer, but copy constructor accepts const reference to an INSTANCE (`*this`) — Dmitry Sazonov, Jun 14 '17 at 14:18
Totally unrelated to your query, but very related to the question, please take some time to [read about how to ask good questions](http://stackoverflow.com/help/how-to-ask). — Some programmer dude, Jun 14 '17 at 14:19
https://stackoverflow.com/questions/645994/why-this-is-a-pointer-and-not-a-reference — Cody Gray - on strike, Jun 14 '17 at 14:20

score 4 · Accepted Answer · answered Jun 14 '17 at 14:30

4

this is a pointer to the object. The copy constructor requires a reference to the object. The way you convert a pointer to a reference is with the dereferencing * operator.

answered Jun 14 '17 at 14:30

Mark Ransom

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I have come across some C++ code.Why we have to use *this in block instead of this?

1 Answers1