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From: matteo.bordin@gmail.com
Newsgroups: comp.lang.ada
Subject: Re: prohibit certain generic instantiations in Ada 2005
Date: 11 Feb 2006 00:04:44 -0800
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Date: 2006-02-11T00:04:44-08:00
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I will provide a proper example in C++. With this code I can prohibit
instantiation of template My_Class with T=int.

class Checker{
public:
  static void check(float){};
private:
  static void check(int){};
};

template <class T>
class My_Class{
public:
My_Class(){
  T t;
  Checker::check(t);

}
};

int main(){

  My_Class<int> mc = My_Class<int>(); //COMPILE TIME ERROR!!!!
  //The error comes from the fact that Checker::check(int) is private
  My_Class<float> mc2 = My_Class<float>(); //OK!!!
};

When I said that the compilation model for template of Ada is similar
to C++, I meant in regards to compile-time code generation (opposed to
the model of Java generics). In both languages (Ada and C++), templates
can be used as a generative environment.
I just want to know f here is a way to reproduce the C++ code I
provided in Ada (2005).

Thank you