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  1. PO
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    <p>To add a bit more to what the posters above me said:</p> <p>You can not have a partially specialized member function in a template class unless the whole class is partially specialized. </p> <p>In other words, if you are OK with the notion of making a partial specialization for the whole DB class if V is a string, you can do something like</p> <pre><code>template&lt;typename K&gt; class DB&lt;K, string&gt;{ //rest of your stuff here } </code></pre> <p>EDIT:</p> <p>With regards to what Joachim Pileborg, here is an alternative that does not require you to reimplement your whole DB Class. I've ommited some details, but the idea should be clear:</p> <pre><code>template&lt;typename K, typename V&gt; class AbstractDb { public: bool Retrieve(const K&amp;, V&amp;) const { std::cout &lt;&lt; "Retrieve for K and V" &lt;&lt; std::endl; return true; }; }; template&lt;typename K, typename V&gt; class Db: public AbstractDb&lt;K, V&gt;{ public: bool SimpleRetrieve(const K&amp;, const V&amp;) const {std::cout &lt;&lt; "Generic Db2 Simple Retrieve" &lt;&lt; std::endl; return true;}; }; template&lt;typename K&gt; class Db&lt;K, std::string&gt; : public AbstractDb&lt;K, std::string&gt;{ public: bool SimpleRetrieve(const K&amp;, const std::string&amp;) const {std::cout &lt;&lt; "SPecialized Db2 Simple Retrieve" &lt;&lt; std::endl; return true;}; }; int main() { Db2&lt;int, int&gt; db; int a = 4, b = 5; db.SimpleRetrieve(a,b); db.Retrieve(a,b); Db2&lt;int, std::string&gt; specdb; std::string str = "abcd"; std::string str2 = "abcd2"; specdb.SimpleRetrieve(a, str); specdb.Retrieve(a, str2); return 0; } </code></pre> <p>The output of that is:</p> <pre><code>Generic Db2 Simple Retrieve Retrieve for K and V SPecialized Db2 Simple Retrieve Retrieve for K and V </code></pre> <p>You would put your functions that need to be specialized in DB, and the ones that don't - in abstract DB.</p>
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    1. POSelectively override functions of templated class
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    1. USdivinas
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    1. COTo not have to re-implement every method in the class, the OP could make a base-class which have all but the `SimpleRetreive` function, and then the generic and specialization classes inherits from the base class.
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      1. USSome programmer dude
    2. CO@divinas : if we start with a partially specialized class , can i extend specific functions to templatize both arguments , some thing like first define a partial templated class `template<typename K> class Db { fun(K &,string& V; template<typename K,typename V> fun(K&,V&); }`
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      1. USShashi
    3. COI'm not 100% sure I understand your question correctly. You can have normal templated functions inside your partially specialized class, and they will behave like normal templated functions. So yes, you can have a templated function fun, that will depend on some template argument that is not part of the specialization of the class, but they will be distinct.
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