functional

The core principles of functional programming are immutability, pure functions, and composition. Applying these concepts avoids data mutation, enhances code predictability, and makes your codebase easier to test and maintain.

You replace imperative loops with functional array methods by using `map`, `filter`, and `reduce`. These methods process arrays immutably, avoiding data mutation and producing more readable, functional code structures.

Pure functions and composition are used over inheritance to make code easier to test and reuse. Composition allows you to build complex behaviors by combining simpler functions without relying on rigid class hierarchies.

You do not need a functional programming library to learn these patterns. This approach focuses on practical application and fundamental principles without delving into heavy abstractions, allowing you to apply patterns using standard language features.

Options objects improve functional programming readability by handling function parameters as named properties. This reduces ordering dependencies, makes function calls self-documenting, and clarifies the intent without needing extra comments.

You should avoid data mutation whenever you need predictable code behavior and maintainability. Embracing immutability ensures that data structures remain unchanged after creation, preventing unintended side effects and simplifying debugging.