In lesson , you learned that a pointer is a variable that holds the address of another variable. Function pointers are similar, except that instead of pointing to variables, they point to functions! Consider the following function: int foo() { return 5; } Identifier foo is the function’s name. But …
A is a default value provided for a function parameter. For example: void print(int x, int y=10) // 10 is the default argument { std::cout << “x: ” << x << ‘\n’; std::cout << “y: ” << y << ‘\n’; } When making a function call, the caller can optionally …
Consider the following function: int add(int x, int y) { return x + y; } This trivial function adds two integers and returns an integer result. However, what if we also want a function that can add two floating point numbers? This add() function is not suitable, as any floating …
Consider the case where you need to write some code to perform some discrete task, like reading input from the user, or outputting something to a file, or calculating a particular value. When implementing this code, you essentially have two options: Write the code as part of an existing function …
In prior lessons, we’ve covered two different ways to pass an argument to a function: pass by value () and pass by reference (). Here’s a sample program that shows a std::string object being passed by value and by reference: #include <iostream> #include <string> void printByValue(std::string val) // The function …
In the previous lessons, we introduced lvalue references () and lvalue references to const (). In isolation, these may not have seemed very useful — why create an alias to a variable when you can just use the variable itself? In this lesson, we’ll finally provide some insight into what …
Author’s note Sorry for the inconvenience, but this lesson was deprecated when the rewrite of Chapter 9 was deployed on Jan 18, 2021. The content of this lesson has been integrated into lesson .
The void pointer, also known as the generic pointer, is a special type of pointer that can be pointed at objects of any data type! A void pointer is declared like a normal pointer, using the void keyword as the pointer’s type: void* ptr {}; // ptr is a void …
Author’s note Sorry for the inconvenience, but this lesson was deprecated when the rewrite of Chapter 9 was deployed on Jan 18, 2021. The content of this lesson has been integrated into lesson .
Member selection for structs and references to structs In lesson , we showed that you can use the member selection operator (.) to select a member from a struct object: #include <iostream> struct Employee { int id {}; int age {}; double wage {}; }; int main() { Employee joe …
