C++ References

	Inline Functions

Overview

When one function calls another, the calling function must send a request to the called function that would process it and return the necessary value, if any. C++ allows you to implement a function so that, when it is called, a copy of the whole function is placed where the function is being called. This means that the calling functions doesn't send a request to the function that performs the assignment: the function itself is accessed where it is needed.

To create an inline function, type the inline keyword to its left when declaring the function. Here is an example:

#include <iostream>

using namespace std;



inline double Sum(const double * Numbers, const int Count)

{

	double s = 0;



	for(int i = 0; i < Count; i++)

		s += Numbers[i];



	return s;

}



int main()

{

	double Nbr[] = { 15.66, 18, 25, 128.62, 12.06, 22.18 };

	double Total = Sum(Nbr, 6);



	cout << "Sum = " << Total << endl;



	return 0;

}

If you first declare a function that would be defined somewhere else, when implementing the function, you can type or omit the inline keyword:

#include <iostream>

using namespace std;



inline double Sum(const double * Numbers, const int Count);



int main()

{

	double Nbr[] = { 15.66, 18, 25, 128.62, 12.06, 22.18 };

	double Total = Sum(Nbr, 6);



	cout << "Sum = " << Total << endl;



	return 0;

}



inline double Sum(const double * Numbers, const int Count)

{

	double s = 0;



	for(int i = 0; i < Count; i++)

		s += Numbers[i];



	return s;

}