Difference Between Struct and Typedef Struct in C++
This small article will discuss the keyword typedef in C++. We will also discuss the difference between a simple struct and a typedef struct in C++.
the typedef Keyword in C/C++
The typedef is a keyword in C/C++ used for giving new names or aliases to data types. These data types can be primitive (e.g., int, float, etc.) or non-primitive or user-defined defined data types (e.g., a class, a struct, or a union).
The typedef keyword is used mainly with user-defined data types that are somewhat complicated to use in the program or have names poorly related to the program context.
The syntax for declaring typedef for the primitive int data type is as follows:
typedef int negative_int;
Now, whenever we must declare an int variable in the program, we can do that with the name negative_int like this:
#include <iostream>
using namespace std;
int main() {
cout << "Welcome to the typedef tutorial" << endl;
typedef int negative_int; // typedef keyword use
negative_int num = -7;
cout << "The number is: " << num << endl;
return 0;
}
The output of this code will be:
Welcome to the typedef tutorial
The number is: -7
Difference Between struct and typedef struct in C++
There is no distinction between struct and typedef struct in C++ since as long as another declaration with the same name does not obscure the name, all structs, unions, enums, and class declarations behave as these are implicitly typedef‘ed.
The C language used typedef struct because, in C, whenever you need to create an object of struct, it is compulsory to use the struct keyword every time. Therefore, typedef is helpful where you can use struct only by its name.