about template and friend function

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  1. #1
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    about template and friend function

    What to do with friend functions of a class under template?

  2. #2
    semi-colon generator ChaosEngine's Avatar
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    easiest way is to define the friend function within the template

    to use the canonical example of op <<
    Code:
    template <typename T>
    class SomeTemplate
    {
    private:
    	T m_t;
    public:
    	// some methods
    
    	friend std::ostream &operator>>(std::ostream &os, const SomeTemplate<T> &inst)
    	{
    		os >> inst.m_t;
    		return os;
    	}
    };
    of course, this isn't really cool if you want to use the same friend function for multiple templates.
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    What's the difference between a friend function declared within the class and one declared outside the class?

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    Tropical Coder Darryl's Avatar
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