Question

What is a global constant? Is it permissible to use global constants in a program?

Short answer

Answer: Yes, it is permissible to use global constants in a program. They can be useful when a constant value is needed throughout a program. However, it's important to use them judiciously to avoid making the code difficult to understand, maintain, and scale. Appropriate scenarios for using global constants include constants related to mathematical operations, configuration values that don't change during the execution of the program, and constants for units conversions or lookup tables that do not change throughout the execution of the program.

Step-by-step solution

Define Global Constant

A global constant is a constant value that is defined outside of any function, class or module, and is accessible from all parts, making it available throughout the entire lifecycle of a program. These constants are typically useful for defining values that remain constant, such as pi, while freeing developers from the need to pass these values explicitly through function parameters.

Permissibility of Global Constants

Yes, it is permissible to use global constants in a program. They can be useful when a constant value is needed throughout a program. However, it's important to use them judiciously. Overuse of global constants can make the code difficult to understand, maintain, and scale, as it introduces unnecessary complexity and potential for bugs due to unintended side effects.

Appropriate Scenarios for Global Constants

Some appropriate scenarios for using global constants are: 1. Constants related to mathematical operations, like pi, e, etc. 2. Configuration values that don't change during the execution of the program, such as the version number, application name, or default settings. 3. Constants for units conversions or lookup tables that do not change throughout the execution of the program. In summary, it is permissible to use global constants in a program, but they should be used with caution and only when necessary. Always consider whether a constant should be global or scoped more narrowly within a function, class, or module.