Templates

[Raj90]

template<int,class T>
class MyClass {
public:
    T buff[10];
    T TestFunction(T val) {return buff[val];}
};

int main()
{
    struct Mystruct {
        int val1;int val2
    };

    Myclass<10,Mystruct> myObj;
}

How to assign the data to val1 and val2 and how to access and pass as argument(struct) to Testfunction?

[2kaud]

Apart from typing errors, the code in post #1 does not initialise the array buff. Consider:

template<int SZ, class T>
class MyClass {
public:
	MyClass() {}
	T buff[SZ] {{1,2}, {3, 4}, {5, 6}};
	T TestFunction(int val) { return buff[val]; }
};

int main()
{
	struct Mystruct {
		int val1; int val2;
	};

	MyClass<10, Mystruct> myObj;

	auto c = myObj.TestFunction(1);

	cout << c.val1 << " " << c.val2 << endl;
}

Note that this test code initializes the contents of buff in the templated class assuming knowledge of type T. You'd probably want a constructor for MyStruct and have a constructor or member function for MyClass for buff initialisation.

[Raj90]

Apart from typing errors, the code in post #1 does not initialise the array buff. Consider:

template<int SZ, class T>
class MyClass {
public:
	MyClass() {}
	T buff[SZ] {{1,2}, {3, 4}, {5, 6}};
	T TestFunction(int val) { return buff[val]; }
};

int main()
{
	struct Mystruct {
		int val1; int val2;
	};

	MyClass<10, Mystruct> myObj;

	auto c = myObj.TestFunction(1);

	cout << c.val1 << " " << c.val2 << endl;
}

Note that this test code initializes the contents of buff in the templated class assuming knowledge of type T. You'd probably want a constructor for MyStruct and have a constructor or member function for MyClass for buff initialisation.

Ya i got your point.but if i have the following code then how to access the following functions

template<int size,class T>
class MyClass {
public:
        MyClass(const T &val)//parameterized constructor
        { globalVal = val;}
        T buff[10];
    void TestFunction(T val) { buff[index] = val;index++}//assume index will be reset in some other function
    T operator[](int localvalue){return buff[localvalue];}
private:
  int globalval;
};

int main()
{
    struct Mystruct {
        int val1;int val2
    };

    Myclass<10,Mystruct> myObj(Mystruct&);//so in this fucntion how to call operator[] and Testfunctions using  myobject and how to assign the data to val1 and val2?
}

[2kaud]

That code has some issues. Have you tried compiling it?

In MyClass, val is a const ref to type T, but is assigned to a type int.

You can't pass Mystruct as a myobj initialisation value, as Mystruct is a type.

[Raj90]

That code has some issues. Have you tried compiling it?

In MyClass, val is a const ref to type T, but is assigned to a type int.

You can't pass Mystruct as a myobj initialisation value, as Mystruct is a type.

There is no compiling issues with the code.. as i tried before posting.

straight forward query.
Myclass<10,Mystruct> myObj();--> what should i pass as argument ,if i want to access the structure?

[2kaud]

int main()
{
    struct Mystruct {
        int val1;int val2
    };

    Mystruct mys;

    Myclass<10,Mystruct> myObj(mys);
}

[Raj90]

How can we add parameterised Constructor to the Structure, for Example:

MyClass
{
};
struct Mystruct
{
int val1;
int val2;
 Myclass(/*to be added here*/);
}

Need to assign values to the val1 and val2?

[VictorN]

How can we add parameterised Constructor to the Structure, for Example:

MyClass
{
};
struct Mystruct
{
  int val1;
  int val2;
  Myclass(/*to be added here*/);
}

Need to assign values to the val1 and val2?

"parameterised Constructor" for the struct Mystruct or for MyClass?
And BTW, what is MyClass?

[2kaud]

How can we add parameterised Constructor to the Structure, for Example:

MyClass
{
};
struct Mystruct
{
int val1;
int val2;
 Myclass(/*to be added here*/);
}

Need to assign values to the val1 and val2?

You add a constructor to the class/struct that takes the values you want to assign. Eg:

struct MyStruct
{
	int val1;
	int val2;

	MyStruct(int v1, int v2) : val1(v1), val2(v2) {}
};


int main()
{
	MyStruct mys(3, 4);
}