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POSpecialization of casting operator to template argument
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copied!<p>I can't find this question answered in any other place, so I finally decided to ask. I have a C++ templated class that includes a casting operator to the type of one of the arguments:</p> <pre><code>template <class E, class B> class bar { private: B innerVal_; [...] public: /* Casting to the type of the 2nd template argument */ operator B() const { return innerVal_; }; // default implementation provided }; </code></pre> <p>However, I need to provide a specialization of this casting operator for some specific template arguments, for instance:</p> <pre><code>template<> bar<concreteType,int>::operator int() // <-- whoops, error! { [...] } </code></pre> <p>The thing is that, no matter how I specify the syntax of the casting operator, gcc consistently returns me an error referred to the declaration of the function. The most common one is:</p> <blockquote> <p>error: template-id ‘operator int<>’ for ‘bar< concreteType, int>::operator int()’ does not match any template declaration.</p> </blockquote> <p>Which I got with these lines:</p> <ul> <li>Defining the casting operator as "operator int()"</li> <li>Using "operator typeB()", after declaring in the original template a line "typedef B typeB;"</li> </ul> <p>I also played around with the "typename" keyword, with template brackets, and made some other desperate attempts. All of them result in bizarre errors --that I'm not going even to paste here.</p> <p>Am I losing some obvious detail? Do you have any hint/pointer for me? Any help will be useful.</p>

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