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POAmbiguous template arguments not excluded by enable_if
 

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  1. POAmbiguous template arguments not excluded by enable_if
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    <p>I want to automatically choose the right pointer-to-member among overloaded ones based on the "type" of the member, by removing specializations that accept unconcerned members (via enable_if).</p> <p>I have the following code:</p> <pre><code>class test; enum Type { INT_1, FLOAT_1, UINT_1, CHAR_1, BOOL_1, INT_2, FLOAT_2, UINT_2, CHAR_2, BOOL_2 }; template&lt;typename T, Type Et, typename func&gt; struct SetterOk { static const bool value = false; }; template&lt;typename T&gt; struct SetterOk&lt;T,INT_1,void (T::*)(int)&gt; { static const bool value = true; }; template&lt;typename T&gt; struct SetterOk&lt;T,FLOAT_1,void (T::*)(float)&gt; { static const bool value = true; }; template&lt;typename T&gt; struct SetterOk&lt;T,UINT_1,void (T::*)(unsigned int)&gt; { static const bool value = true; }; template&lt;typename T&gt; struct SetterOk&lt;T,CHAR_1,void (T::*)(char)&gt; { static const bool value = true; }; template&lt;typename T&gt; struct SetterOk&lt;T,BOOL_1,void (T::*)(bool)&gt; { static const bool value = true; }; template&lt;typename T&gt; struct SetterOk&lt;T,INT_2,void (T::*)(int,int)&gt; { static const bool value = true; }; template&lt;typename T&gt; struct SetterOk&lt;T,FLOAT_2,void (T::*)(float,float)&gt; { static const bool value = true; }; template&lt;typename T&gt; struct SetterOk&lt;T,UINT_2,void (T::*)(unsigned int, unsigned int)&gt; { static const bool value = true; }; template&lt;typename T&gt; struct SetterOk&lt;T,CHAR_2,void (T::*)(char,char)&gt; { static const bool value = true; }; template&lt;typename T&gt; struct SetterOk&lt;T,BOOL_2,void (T::*)(bool,bool)&gt; { static const bool value = true; }; template &lt;bool, class T = void&gt; struct enable_if {}; template &lt;class T&gt; struct enable_if&lt;true, T&gt; { typedef T type; }; template&lt;typename T, Type Et&gt; struct Helper { template&lt;typename U&gt; static void func(U method, typename enable_if&lt;SetterOk&lt;T,Et,U&gt;::value&gt;::type* dummy = 0) { } }; class test { public: void init() { Helper&lt;test,INT_2&gt;::func(&amp;test::set); } void set2(int); void set(int); void set(int,int); void set(float,float); }; int main() { test t; t.init(); return 0; } </code></pre> <p>I'm expecting it to choose the right function between all possible. The problem is that the compiler says "cannot deduce template argument as function argument is ambiguous".</p> <p>It seems I don't know how to use enable_if, because if so the compiler would only allow the specialization if the specified function has the right type...</p> <p>Note that I want to have C++03 solutions (if possible) - my code must compile on some old compilers.</p> <p>Thanks in advance</p>
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    1. COTHe compiler simply doesnt kow which of the set overloads to chose to even start the instantiationing processing
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    2. COI think I've found an alternative solution to your problem. Please check my answer below.
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      1. USAgentlien
 

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