Working through the course Haskell MOOC has been an educational experience, introducing me to the world of functional programming through the robust Haskell language. The course, designed for both beginners and even those familiar with functional programming, has provided a comprehensive foundation in Haskell, covering everything from basic syntax to advanced features like higher-order functions and algebraic data types.
The course itself is divided into two individual large parts. It includes an excellent free online course material with examples and exercises.
Working on the exercises involves knowing how to use the command line, and basic usage of the Git version control system.
There are two parts with a total of 16 lectures. Part 1 covers the basics of Haskell syntax and features sticking to pure functional programming, without side-effects. I/O (input-output) and Monads will be introduced in Part 2.
monad: a design pattern used to handle computations in a sequence. It allows for chaining operations while managing side effects, encapsulating values, and providing a way to apply functions to these values.
All 16 lectures are roughly the same size, but some have more material than others. Each lecture set ends with 10-30 small programming exercises on the topics of the lecture. The course is completed by solving all the exercises.
※ My solution is at the end of the article.
Haskell is inherently functional. In Haskell, the primary building blocks are functions. Unlike imperative languages, where you write a series of instructions to change the state, Haskell focuses on the application of functions. This paradigm shift brings a unique set of advantages, especially in terms of code clarity and ease of reasoning.
One of the most compelling aspects of Haskell is its purity. Functions in Haskell do not have side effects, meaning they do not alter any state or interact with the outside world within their execution. This purity ensures that given the same inputs, a function will always return the same output, making Haskell code more predictable and easier to debug.
Haskell employs lazy evaluation, meaning that expressions are only evaluated when needed. This allows for the creation of infinite data structures and can lead to performance optimizations by avoiding unnecessary calculations.
Haskell’s type system is both strong and expressive. Every value and expression in Haskell has a type, which is checked at compile time, eliminating a whole class of runtime errors. Additionally, Haskell's compiler can infer types, reducing the need for explicit type annotations while maintaining type safety.
Haskell’s unique features make it suitable for a variety of applications:
TypeScript, a superset of JavaScript, brings static typing to the dynamic world of JavaScript. While TypeScript improves the reliability and maintainability of JavaScript code, it remains fundamentally imperative and object-oriented, focusing on classes and mutable state.
Go, developed by Google, is designed for simplicity and efficiency in systems programming. It is an imperative language with a focus on concurrency, making it popular for backend services and cloud applications.
The Haskell MOOC course has provided a deep understanding of Haskell’s functional programming paradigm, emphasizing its purity, laziness, and strong typing. While Haskell’s approach differs significantly from languages like TypeScript and Go, these differences also highlight its strengths, particularly in areas requiring mathematical precision and reliability. I think by continuing to learn and explore Haskell, it will strengthen my overall skills as a programmer by giving me opportunities to think a bit differently compared to the usual status quo of languages. Also I feel I can utilize the some of the code practices used in Haskell with other languages as well.