Functional Programming In Scala Guide

Scala provides several built-in tools that make functional patterns elegant and concise:

Functional Programming (FP) in Scala isn't just about using a different syntax—it’s about changing how you think about problems. By treating programs as a series of mathematical transformations rather than a sequence of changes to a shared state, you can write code that is more reliable, easier to test, and naturally thread-safe. 1. The Core Pillars of Scala FP

: A function is "pure" if it always returns the same output for the same input and has no side effects (like printing to a console or updating a database). Functional Programming in Scala

: Once a value is created, it never changes. Instead of modifying a list, you create a new one with the desired changes. This eliminates entire classes of bugs related to shared mutable state.

: Think of this as "switch statements on steroids." It allows you to deconstruct data structures like Case Classes or Options with type safety. Scala provides several built-in tools that make functional

: This means you can replace a function call with its resulting value without changing the program's behavior. This makes reasoning about complex code much simpler. 2. Powerful Scala Features for FP

def buyCoffee(cc: CreditCard): Coffee = val cup = new Coffee() cc.charge(cup.price) // Side effect: hits the bank API immediately cup Use code with caution. Copied to clipboard Learning Functional Programming with Scala | by Ryan Susana The Core Pillars of Scala FP : A

: In Scala, functions are first-class citizens. You can pass them as arguments to other functions (like map , filter , or flatmap ) or return them as values.