FizzBuzz Functional Fun in Scala

UpdatedNovember 29, 2023

•4 min read•View as Markdown

Hans L'Hoest

I write about: Software architecture and engineering, Better software better. DDD, Scala and Rust

Part of seriesFizzBuzz Fun in Scala

Comments

Join the discussion

No comments yet. Be the first to comment.

FizzBuzz Fun in Scala

Part 1 of 6

Some fun and exploring of FizzBuzz implementations in functional programming style and Scala 3.

Up next

FizzBuzz Functional Fun in Scala 3

Nearly a decade ago, I wrote a post about implementing FizzBuzz in a more functional manner, which also happened to be the final entry on a blog I started that year. Now, I want to dedicate more time to writing, and rebooting my blog seems to be a go...

More from this blog

The Unification of Commands and Skills in Claude Code

In Claude Code, a skill is a modular function-like component that can process requests — like /code-review or /commit. As of version 2.1.1, these skills can be directly invoked through slash commands. So a code-review skill can also be invoked direct...

Jan 19, 20267 min read

Agent Chisels: My LLM Agent Skills and Workflows

I have been meaning to share more about my LLM workflows and tooling for a while, partly to have a reference for conversations, but mostly to learn in public. Agent Chisels is where I will be sharing the custom artefacts (primarily skills, with comma...

Jan 13, 20263 min read

My Best Technical Decision of 2025: Moving to Proton for Peace of Mind

This year I bit the bullet and moved mail, calendar and drive from Google to Proton. Knowing that my family is not being profiled when, for example, I plan a doctor's appointment feels liberating. Sure, there were fun and useful technical improvement...

Dec 22, 20253 min read

Implementing an Urgent Feature with Opencode, Claude, and Zed

This is a short post to share a positive experience I had using an LLM agent to quickly add a feature to an existing personal CLI time-tracking application. Below, I describe how I added it using Zed, Opencode and Claude. To start, I wasn't even sure...

Dec 17, 20255 min read

TIL rules to remember

I have been writing "Today I Learned" posts (TILs) for a few weeks now and I started writing them as a complement to long form blogging. But I found myself spending 45-60 minutes, sometimes longer, per TIL instead of 15-25. This defeated the purpose ...

Dec 15, 20251 min read

Hans L'Hoest

35 posts

def fizzbuzz(s: Int): List[String] = { def shout(i: Int): String = if (i % 15 == 0) "FizzBuzz" else if (i % 3 == 0) "Fizz" else if (i % 5 == 0) "Buzz" else i.toString val fb: Stream[String] = Stream.from(1).map(i => shout(i)) (fb take s).toList }

import org.scalacheck.Gen import org.scalatest.FunSuite import org.scalacheck.Prop.forAll import org.scalatest.prop.Checkers class FizzBuzzTest extends FunSuite with Checkers { test("fizzbuzz") { val fb = fizzbuzz(100) val range = Gen.choose[Int](1, 100) val fizzbuzzProperty = forAll(range) { n => if (n % 15 == 0) fb(n - 1) == "FizzBuzz" else if (n % 5 == 0) fb(n - 1) == "Buzz" else if (n % 3 == 0) fb(n - 1) == "Fizz" else fb(n - 1) == n.toString } check(fizzbuzzProperty) } }

def fizzbuzz(s: Int): List[String] = { // helper method inspired by haskell, cycle a list infinitely, def cycle(xs: List[String]): Stream[String] = Stream.continually(xs).flatten val numbers = Stream.from(1) // a infinite cycle of "", "", "Fizz" val fizzes = cycle(List("", "", "Fizz")) // a infinite cycle of "", "", "", "", "Buzz" val buzzes = cycle(List("", "", "", "", "Buzz")) // zip the fizzes and buzzes, and concatenate them, result is "", "", "Fizz", "", "Buzz", "Fizz", ... val pattern = fizzes zip buzzes map { case (f, b) => f + b } // zip numbers with the pattern, if the pattern is empty keep the number, otherwise keep the pattern val numbersAndPattern = numbers zip pattern map { case (n, p) => if (p.isEmpty) n.toString else p } numbersAndPattern take s toList }

Command Palette

Comments

FizzBuzz Fun in Scala

FizzBuzz Functional Fun in Scala 3

More from this blog