Understanding Functional Programming: The Core Concepts

March 14, 2024

This lesson will introduce you to the fundamental concepts of functional programming and how they are applied in Haskell. We will explore immutability, higher-order functions, and pure functions.

Immutability

In functional programming, immutability refers to the concept that once a value is assigned to a variable, it cannot be changed. This means that variables are not updated in place, but rather new values are created based on existing ones. In Haskell, all data is immutable, and this leads to safer and more predictable code.

Higher-Order Functions

Higher-order functions are functions that can take other functions as arguments or return functions as results. In Haskell, functions are first-class citizens, which means they can be treated as values. This allows for powerful abstractions and the composition of functions, leading to concise and expressive code.

Pure Functions

Pure functions are functions that, given the same input, will always return the same output and have no side effects. This property makes them predictable and easy to reason about. In Haskell, the emphasis on pure functions facilitates referential transparency, which is the ability to replace a function call with its result without changing the program’s behavior.