Advanced C++ Programming Cookbook

Example 6

Example 6 demonstrates the principle of least surprise as follows:

#include <iostream>int add(int a, int b){ return a + b; }int Sub(int a, int b){ return a - b; }int main(void){    std::cout << "The answer is: " << add(41, 1) << '\n';    std::cout << "The answer is: " << Sub(43, 1) << '\n';    return 0;}

As shown in the preceding code, we have implemented two different APIs. The first adds two integers and returns the results while the second subtracts two integers and returns the results. The issue with the subtract function is two-fold:

• The addition function is in lowercase while the subtraction function is in uppercase. This is not intuitive and users of the APIs would have to learn which APIs are in lowercase and which are in uppercase. ...