c++ - Restriction of access to function -

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• std::enable_if conditionally compile member function 6 answers

i have generic class function want restrict instances of floating point types only, @ compile time. shown in example below:

template <typename t> class classname {     // instance variables, etc..      void some_method()     {         // stuff, floating point types     } } 

how make compiler reject usage of some_method classname of non-floating point types?

i have been looking @ sfinae can't work, after several hours of failing i'm asking help.

thanks :)

you can use combination of std::is_floating_point , std::enable_if enable function floating point types:

#include <type_traits>  template <typename t> class classname {     // instance variables, etc..  public:   template<typename t2 = t,            typename = typename std::enable_if< std::is_floating_point<t2>::value >::type>   void some_method()   {      // stuff, floating point types   }  };  int main() {   classname<double> d; // ok   d.some_method();     // ok   classname<int> i;    // ok   i.some_method();     // error }