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Using swap idiom for exception safety in a constructor

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Hi, I want to ensure exception safety inside a constructor by creating a temporary object and then swapping it with *this:

class Test {
public:
    Test(int value) : p(0)
    {
        Test tmp;
        tmp.initialize(value); // In case of exception, tmp is destroyed
        swap(tmp);
    }

    ~Test() 
    { 
        if (p) delete p; 
    };

    swap(Test& other) {...}

private:
    Test() : p(0) {} 
    
    void initialize(int value) 
    { 
       p = new X(value, ...);
       // and more members...
    }

private:
    X * p;
    // And many more members...
};

I wanted to know:
a) Is this a common approach? 
b) What other options do you recommend when this is not possible (e.g. Test has pure-virtual methods so I can't instantiate the tmp object)?

Thanks

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Using swap idiom for exception safety in a constructor Alex <acamposr@gmail.com> - 2012-04-03 17:52 -0700
  Re: Using swap idiom for exception safety in a constructor Howard Hinnant <howard.hinnant@gmail.com> - 2012-04-03 19:52 -0700
  Re: Using swap idiom for exception safety in a constructor goran.pusic@gmail.com - 2012-04-04 05:07 -0700
  Re: Using swap idiom for exception safety in a constructor "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2012-04-04 23:19 +0200

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