Inline function in C++

Inline functions in C++ are functions that are expanded by the compiler at the point where they are called, rather than being executed as a separate function call. This can increase program speed and performance.

Syntax

inline return_type function_name(parameters) {
    // function code
}

Example

#include <iostream>
using namespace std;

inline int square(int x) {
    return x * x;
}

int main() {
    int num = 5;
    cout << "Square of " << num << " is " << square(num) << endl;
    return 0;
}

Output

Square of 5 is 25

Explanation

In the above example, we have defined an inline function called "square" which returns the square of a given number. When the function is called in the main function, the compiler expands the code of the function inline rather than performing a separate function call, which can improve program performance.

Use

Inline functions are useful when you have small functions that are called frequently. By declaring them as inline functions, you can avoid the overhead of function calls and improve program performance. However, inline functions should only be used for small functions, as larger functions can actually decrease program performance due to increased code size.

Important Points

• Inline functions are expanded by the compiler at the point where they are called.
• Inline functions can improve program performance for small functions.
• Inline functions should only be used for small functions, as larger functions can decrease program performance.
• The use of inline is only a suggestion to the compiler and may be ignored.

Summary

Inline functions in C++ can improve program performance by avoiding the overhead of function calls. They are especially useful for small functions that are called frequently. However, inline functions should only be used for small functions and the use of inline is only a suggestion to the compiler and may be ignored.