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Passing a function as an argument to a class template

Not knowing the type of function, I declare its pointer below using the method and initializing the function pointer.

template<typename T>
struct Declare { typedef T Type; }; // for declaring any func ptr

void fun () {}

int main ()
{
  Declare<fun>::Type pf = &fun;  // can't use C++0x 'auto'
}

However, it gives compiler error as error: expected a type, got ‘fun’. Although the type of any method is known at compile time. Is it invalid to pass a function to a class templateas described above?

[Note: replacing funwith void (*)()works fine. But this is not what is needed.]

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2 answers

Is it not valid to pass a function to a class template as described above?

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Declare obj(&fun);

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EDIT:

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Declare<decltype(&fun)>::Type pf = &fun;  
pf(); //call the function

: http://ideone.com/

Declare, :

decltype(&fun) pf = &fun; 
pf(); //call the function
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BOOST_AUTO(var1,hello()); // type of var1 == int
BOOST_TYPEOF(hello()) var2 = hello(); // same

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void myfunc(FPtr otherfunc){
  // use otherfunc
}

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