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POoverloading operator !=
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copied!<p>I wrote a smarter pointer class. And to make the following code correct </p> <pre><code>ZhjSmartPointer<int> a(new int); assert(a != NULL); </code></pre> <p>I overload the != operator like this: </p> <pre><code>bool operator !=(T *ptr) const; </code></pre> <p>however, this leads to a compile error like this: </p> <blockquote> <p>ZhjSmartPointer.h:132: note: candidate 1: bool ZhjSmartPointer::operator!=(T*) const [with T = Test] test.cpp:41: note: candidate 2: operator!=(int, int) </p> </blockquote> <p>I'm confuse with how a <code>ZhjSmartPointer</code> can be transfered into an <code>int</code></p> <p>The Code of SmartPointer class is like this:</p> <pre><code>template <typename T> class ZhjSmartPointer { public: ZhjSmartPointer(); explicit ZhjSmartPointer(T *ptr); ZhjSmartPointer(const ZhjSmartPointer &smartPtr); ZhjSmartPointer &operator =(const ZhjSmartPointer &smartPtr); ~ZhjSmartPointer(); operator bool() const; T &operator *() const; T *operator ->() const; bool operator ==(const ZhjSmartPointer &smartPtr) const; bool operator !=(const ZhjSmartPointer &smartPtr) const; bool operator ==(T *ptr) const; bool operator !=(T *ptr) const; private: void copyPtr(const ZhjSmartPointer &smartPtr); void deletePtr(); T *ptr_; size_t *refCnt_; }; </code></pre> <p>I guess because I overload the 'bool' operator, 'ZhjSmartPointer -> bool -> int' leads to this problem.Is this right?</p> <p>Sorry,It is just a compile warning, not a error. Someone suggest me not overloading != with parameter(T *), after all, we already have overloaded 'bool'.It will be fine to write codes like these:<br> ZhjSmartPointer a(new int);<br> if (a) { ..........<br> } </p>

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