Functional Programming in Dart

A Deep Dive into Network Responses 🌐 to Handle API Responses with Dart.

Functional programming has transformed how we write software, enabling developers to produce more predictable, maintainable, and error-resistant code. Dart, a versatile language, supports functional programming patterns, which are especially useful for handling asynchronous operations such as API calls.

In this article, we’ll explore functional programming in Dart by comparing a custom class for managing API responses with the popular dartz package. We’ll also cover additional functional programming techniques like map, fold, and Future combinators, giving you a deeper understanding of how to handle data flow effectively.

Why Functional Programming? 🤔

Functional programming promotes writing pure functions, handling data through immutability, and eliminating side effects. This approach makes your code easier to reason about and debug, especially when managing state or asynchronous data such as API responses.

Key Concepts in Functional Programming:

• Immutability: Data structures don’t change; instead, you create new ones with modified values.
• Pure Functions: Functions that don’t modify any outside state and always return the same output for the same input.
• Higher-Order Functions: Functions that take other functions as parameters or return them as results.

These principles are crucial for managing complex flows like handling API responses.

Custom Class for Network Responses: A Hands-On Example 💻

When dealing with API responses, the data returned can either be a success or an error. Instead of writing if-else blocks or using try-catch, functional programming offers a cleaner, more declarative way to handle these outcomes.

Let’s implement a custom class using sealed classes in Dart to manage API responses functionally.

Custom Implementation

sealed class NetworkResponse {
  const NetworkResponse();

  T when<T>({
    required T Function(dynamic data) success,
    required T…