Correct and incorrect variable naming conventions in C++
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This program example demonstrates the correct and incorrect variable naming conventions in C++
/**
* @file main.cpp
* @brief This program demonstrates the correct and incorrect variable naming conventions in C++.
*/
#include <iostream>
using namespace std;
int main() {
// Correct variable naming conventions
int number; ///< Variable names can start with a letter
int Number; ///< Variable names are case sensitive
string NUMBER; ///< Variable names can be in uppercase
float number1; ///< Variable names can contain numbers
bool number_1; ///< Variable names can contain underscores
int number_1_; ///< Variable names can end with an underscore
int _number; ///< Variable names can start with an underscore
int _number_; ///< Variable names can start and end with an underscore
int _1number; ///< Variable names can contain numbers after an underscore
int _1_number; ///< Variable names can contain underscores and numbers
int _1_number_; ///< Variable names can start and end with an underscore and contain numbers
int number1_; ///< Variable names can end with a number and an underscore
// Incorrect variable naming conventions
// int 1number; // Variable names cannot start with a number
// int number$; // Variable names cannot contain special characters
// int number one; // Variable names cannot contain spaces
// int number-one; // Variable names cannot contain special characters
// int number@; // Variable names cannot contain special characters
// int number#; // Variable names cannot contain special characters
return 0;
}
Explanation
The provided C++ code is a simple program designed to illustrate the correct and incorrect conventions for naming variables in C++.
The program begins with the inclusion of the iostream library, which is used for input/output operations. The using namespace std; statement is used to avoid having to prefix standard library components with std::.
#include <iostream>
using namespace std;
The main function is where the execution of the program starts. Inside this function, several variables are declared to demonstrate the correct naming conventions in C++.
int number; ///< Variable names can start with a letter
int Number; ///< Variable names are case sensitive
string NUMBER; ///< Variable names can be in uppercase```
In C++, variable names can start with a letter, are case sensitive, and can be in uppercase. They can also contain numbers and underscores. For example, `number1`, `number_1`, and `number_1_` are all valid variable names.
```cpp
float number1; ///< Variable names can contain numbers
bool number_1; ///< Variable names can contain underscores
int number_1_; ///< Variable names can end with an underscore```
Variable names can also start with an underscore, and they can contain numbers after an underscore. For instance, `_number`, `_1number`, and `_1_number` are all valid variable names.
```cpp
int _number; ///< Variable names can start with an underscore
int _1number; ///< Variable names can contain numbers after an underscore
int _1_number; ///< Variable names can contain underscores and numbers
The program also includes commented-out lines of code that demonstrate incorrect variable naming conventions. In C++, variable names cannot start with a number, contain special characters, or contain spaces.
// int 1number; // Variable names cannot start with a number
// int number$; // Variable names cannot contain special characters
// int number one; // Variable names cannot contain spaces
Finally, the main function returns 0, indicating successful execution of the program.
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