C Constants: An Introduction
In my previous blog post, I discussed variables in C. This time, I want to dive into the concept of constants in C.
Constants in C are similar to variables, but they have a fixed value that cannot be changed during the program’s execution. To declare a constant, you use the const keyword followed by the data type and the value it holds. Here’s an example:
1 | const int age = 37; |
While it’s valid to declare constants using lowercase letters, it is a convention to use uppercase letters. This improves readability and helps distinguish constants from variables. For instance:
1 | const int AGE = 37; |
Another way to define constants in C is by using the #define directive. With this approach, you don’t need to specify a type, an equal sign, or a semicolon. Here’s an example:
1 |
Using the #define approach, the C compiler will infer the type of the constant from the value specified at compile time.
When naming a constant, you follow the same rules as naming variables. The name can contain uppercase or lowercase letters, digits, and underscores. However, it cannot start with a digit. For example, AGE and Age10 are valid constant names, while 1AGE is not.
Understanding how to work with constants in C is essential for writing readable and maintainable code. By following these conventions, you can easily identify and differentiate constants from variables.
Tags: C programming, constants in C, variable naming conventions