Decorators
Decorators are a design pattern and language feature used to modify or extend the behavior of functions, methods, or classes without permanently altering their source code. They are implemented as higher-order functions or special syntax that wrap or annotate target code, enabling reusable cross-cutting concerns like logging, caching, or access control. This pattern is prominent in languages like Python and JavaScript/TypeScript, where it provides a clean, declarative way to add functionality.
Developers should learn decorators to write more modular, maintainable, and DRY (Don't Repeat Yourself) code by separating core logic from auxiliary concerns like validation, timing, or authentication. They are particularly useful in web development for middleware in frameworks (e.g., Flask decorators for routes), in object-oriented programming for method enhancements, and in metaprogramming for dynamic behavior. Using decorators can reduce boilerplate and improve code readability by centralizing common tasks.