Which term defines reusable functions for displaying warning or error messages?

The term that defines reusable functions for displaying warning or error messages is “Helper Function.” Helper functions are designed to encapsulate common functionality, which in this case, pertains to presenting warnings or error messages in a consistent manner throughout the application. These functions streamline the process of message display, reduce redundancy in the codebase, and make it easier to manage how messages are presented to users.

Utilizing helper functions allows developers to implement changes to the messaging format or logic in a single location, thereby increasing maintainability and reducing potential errors that could arise from duplicating similar code in multiple places. Helper functions are especially useful in scenarios where specific, repeated tasks need to be performed consistently, such as displaying error messages that follow a particular format or style.

In contrast, the other options pertain to different concepts within programming and development. Validatable delegate refers to a specific mechanism for performing validations, Validation Rules define the criteria to assess whether data is valid, and Error Handling Protocols typically outline the strategies for dealing with errors rather than focusing on the presentation of messages.