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POC++ Destructor Called Multiple Times
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copied!<p>I'm making a little wrapper class for sqlite. To get data to/from the database I have a class called SQLiteValue. When binding data for a query SQLiteValue instances get created on the stack and passed around a few functions. A skeleton outline of the class is below.</p> <pre><code>class SQLiteValue : public SQLiteObject { private: // stores a pointer to the data contained (could be of varying types) union { int* i; double* d; std::string* s; std::wstring* ws; BYTE* b; } pdata; int type; public: SQLiteValue(const char* val); SQLiteValue(const wchar_t* val); .. and so on for varying types virtual ~SQLiteValue(); }; </code></pre> <p>The object gets created by one of several overloaded constructors. The constructors instantiate a "member" of pdata based on their type. This is the important thing for this class. Now, the problem. I have the constructors overloaded so I get clean method calls and don't need to explicitly call SQLiteValue(xxx). As such I don't really want to use references for functions, so I define them like.</p> <pre><code>void BindValue(const char* name, SQLiteValue value) query->BindValue(":username", "user2"); // the "clean" method call </code></pre> <p>Declaring them like this causes a new object to be instantiated every time (or something similar?) I call a function and so the destructor frees memory allocated for pdata. This is bad.</p> <p>What I'd like to know is this. Is there a better way to achieve what I'm trying to do whilst retaining my clean method calls? At the moment I have private functions which operate by reference which solves the issue, but I don't really like this method. It would be easy for me to forget the reference and I'd end up tracking down this same issue again.</p> <p>Thanks.</p>

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