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#include <iostream>
using namespace std;

template <class T>
class class_template 
{
    	T value1;
		T value2;
	public:
	    class_template (T first, T second)
	    {
	      value1 = first; 
		  value2 = second;
	    }

	// public function
	T getmax()
	{			
		return value1 > value2 ? value1 : value2;
	}
};

int main()
{
	char a = 'A', b = 'B';
  	class_template <int> myobject1 (100, 75);
	class_template <int> myobject2 (123.123, 75.87); 
	class_template <float> myobject3 (123.123, 75.87);	
	class_template <char> myobject4 ('A', 10);	
	class_template <char*> myobject5 (&a, &b);
	class_template <class_template*> myobject6 ((class_template*)0x100, (class_template*)0x200);
	
  	cout << "\n Maximum Value (int)= " << myobject1.getmax();
	cout << "\n Maximum Value (int)= " << myobject2.getmax();
	cout << "\n Maximum Value (float)= " << myobject3.getmax();
	cout << "\n Maximum Value (char)= " << myobject4.getmax();	
	printf("\n Maximum Value (char*)= 0x%08X [a=0x%08X, b=0x%08X]", myobject5.getmax(), &a, &b);
	
	printf("\n Maximum Value (class_template*)= 0x%08X [a=0x%08X, b=0x%08X]", myobject6.getmax(), &myobject1, &myobject2);	
	
	cout << "\n";
	
  	return 0;	
}

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		class_template <class_template*> myobject6 ((class_template*)0x100, (class_template*)0x200);

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		error: template argument 1 is invalid
		error: invalid type in declaration before ‘(’ token
		error: missing template arguments before ‘*’ token
		error: expected primary-expression before ‘)’ token
		error: missing template arguments before ‘*’ token
		error: expected primary-expression before ‘)’ token
		error: initializer expression list treated as compound expression

Code: Select all

#include <iostream>

using namespace std;

//template <class T>
class class_template 
{
    	class_template* value1;
		class_template* value2;
		
	public:
		
		// Constructor 		
	    class_template (class_template* first, class_template* second)
	    {
	      value1 = first; 
		  value2 = second;
	    }

		// public function
		unsigned long getmax()
		{			
			return (unsigned long)(value1 > value2 ? value1 : value2);
		}
};


int main()
{
  	class_template myobject1((class_template*)0x10, (class_template*)0x20);
	class_template myobject2((class_template*)0x30, (class_template*)0x40);
	class_template myobject3(&myobject1, &myobject2);

	printf("\n Maximum Value (class_template*)= 0x%08X [a=0x%08X, b=0x%08X]", myobject3.getmax(), &myobject1, &myobject2);	
	
	cout << "\n";
	
  	return 0;	
}

/* 
output:

 Maximum Value (class_template*)= 0xBFBE87A8 [a=0xBFBE87A8, b=0xBFBE87A0]
 
*/

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template <class T> class class_template; // not a type, but a template.
class_template< int > foo;       // foo has a type
class_template< double > bar;    // bar has a type
class_template baz;              // syntax error

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   class_template <class_template*> myobject6 ((class_template*)0x100, (class_template*)0x200);

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   class_template <class_template<type here*> myobject6 (new class_template<type here>(p, q), new class_template<type here>(r, s));

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   class_template <class_template*> myobject6 ((class_template*)0x100, (class_template*)0x200);

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   class_template <class_template<int>*> myobject6 ((class_template<int>*)0x100, (class_template<int>*)0x200);

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 Maximum Value (int)= 100
 Maximum Value (int)= 123
 Maximum Value (float)= 123.123
 Maximum Value (char)= A
 Maximum Value (char*)= 0x0022CD4F [a=0x0022CD4F, b=0x0022CD4E]
 Maximum Value (class_template*)= 0x00000200 [a=0x0022CD44, b=0x0022CD3C]

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class_template<int> * foo = (class_template<int> *) 0xdeadbeef;

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template < typename T > class MyClass { /* ... */ };