Helper Function in C++ Classes
Last Updated :
06 Jun, 2024
In C++, the users can keep their class methods organized and readable with the help of private helper functions. Helper functions are utility functions that are only accessible within the class. They can't be called externally but can be used by the class's public methods to perform lower-level tasks. In this article, we will learn about using helper functions in C++.
Helper Functions Inside C++ Classes
In C++, helper functions are defined as smaller auxiliary functions designed to perform specific task in a class. These functions are not called directly by the users but by the other functions of the same class. Helper functions enhance the modularity and privacy of the code ensuring that the same piece of code is not written again and again and also that it cannot be externally called.
Syntax
Class class_name{
private:
return_type Function_name(parameters){}
}
where:
- private: is the access specifier for the helper function so that it can't be used externally.
- class_name: is the name of the class to which the helper function belongs.
- Function_name: is the name of the helper function.
- return_type: denotes the return type of the helper function.
Example of Class Helper Function in C++
The following program illustrates how we can use helper functions in a class in C++:
C++
// C++ Program to illustrate the use of using Helper
// Function
#include <iostream>
using namespace std;
class MyClass {
private:
int value;
// Helper function to perform data validation
bool isDataValid(int val)
{
return val > 0 && val < 100;
}
public:
// Constructor
MyClass(): value(0){}
void setData(int data)
{
// Call helper to validate user input
if (isDataValid(data)) {
value = data;
cout << "Data set to " << value << endl;
}
else {
cout << "Invalid data: " << data
<< " Please enter a value between 1 - 99 "
<< endl;
}
}
// Getter function
int getData() { return value; }
};
int main()
{
// Create an object of the class
MyClass obj;
// Set valid data
obj.setData(42);
cout << "Value: " << obj.getData() << endl;
// Set invalid data
obj.setData(-10);
return 0;
}
OutputData set to 42
Value: 42
Invalid data: -10 Please enter a value between 1 - 99
Time Complexity: O(1)
Auxiliary Space: O(1)
Explanation: In the above example, we have defined a helper function isDataValid within the class that acts as helper function for setData method. The helper functions checks if the data provided by the user is within the valid range and then only set the data.
Benefits of Using Helper Functions
Following are some benefits of using helper functions in a class in C++:
- Code Organization: Helper functions helps the user to break down complex logic from public methods into smaller reusable code. This makes the code easier to understand , maintain and debug.
- Reusability: Helper function promotes code reusability. The same helper functions can be used by multiple public methods within a class.
- Abstraction: The helper functions promotes abstraction within a class by hiding the implementation details of the code from outside the class.
- Testing: Private helper functions can be used in unit testing by the public methods directly. The private access specifier ensures that these functions are not available to anyone outside the class.
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