How to Write a Haskell Function in 2025?

Haskell, a purely functional programming language, continues to grow in popularity in 2025. Known for its expressive type system and concise syntax, Haskell offers a unique approach to problem-solving. If you’re interested in learning how to write a Haskell function in 2025, this guide will provide you with an SEO-optimized overview that covers the essentials.
Getting Started with Haskell
Before you start writing Haskell functions, make sure you have Haskell installed on your system. If you’re using Ubuntu, you can follow this guide on Haskell installation.
Understanding Haskell Functions
In Haskell, functions are first-class citizens. This means you can pass functions as arguments, return them, and store them as variables. A typical Haskell function is defined using the functionName :: Type signature and functionName = expression for implementation.








