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PODatatypes and polymorphism
 

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    <p>I have a design question. I want custom datatypes implementing an interface. For example, using templates is simply (maybe next design isn't correct -because I can do a generic class instead of the next- but clarifies my goal):</p> <pre><code>template &lt;typename T&gt; class IDatatype { public: virtual T getData() const = 0; virtual void setData(T pData) = 0; }; class MyChar: public IDatatype&lt;char&gt; { public: void setData(char pData){...} char getData() const{...} private: char _data; }; class MyInt: public IDatatype&lt;int&gt; { public: void setData(int pData){...} int getData() const{...} private: int _data; }; IDatatype&lt;int&gt; *data = new MyInt(); // parametrized interface, bad idea :( data-&gt;getData(); // it works ok </code></pre> <p>From previous classes, it is easy to get the attribute corresponding to each _data class member. My question: </p> <blockquote> <p>Is there any way (change design, etc.) to implement generic setter and getter in IDatatype and for any type and thus manipulate the _data attribute of each class without using templates in the interface?</p> </blockquote> <p>For example: </p> <pre><code>class IDatatype { public: // pure virtual getters and setters for specialized _data fields. Here is my design question. }; class MyChar: public IDatatype { public: void setData(char pData){...}; char getData(){...}; private: char _data; }; class MyInt: public IDatatype { public: void setData(int pData){...}; int getData(){...}; private: int _data; }; IDatatype *intData = new MyInt(); // no parametrized interface! intData-&gt;getData(); // how can I create this method from IDatatype? IDatatype *charData = new MyChar(); charData-&gt;getData(); // the same here </code></pre> <p>NOTE: I have no good english, apologize for any errors :)</p>
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    1. COC++ is not right language for do such things. You cannot do this automatically, only manually, by saving type-identification in object, by creating visitor may be, by store void* (boost::any, boost::variant) as field, etc...
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    2. COSee this [answer](http://stackoverflow.com/a/4233138/1930331). @ForEveR says a lot of what is there.
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