Functional Programming Katas

Getting started

0. install sbt
1. execute sbt in this project folder.
2. select the kata you want to do with project $projectname. For example project simple-lists.
3. execute the tests with test. You may execute ~test for continues test executions.

If you are stuck, you may take a look into the solution branch.

Kata 1 - Simple Lists

The starting point is the SimpleListSpec.scala file. Just uncomment the spec and get started.

The goal of the project is to implement a immutable List data structure. You will learn about immutablity, function passing and recursion.

Feel free to implement your solution first in java and then in scala.

Quick start:

sbt ~simple-lists/test

Kata 2 - Simple Streams

todo

Kata 3 - Simple Errors

todo

Kata 4 - Simple Generators

todo

Kata 5 - Functional Type Classes

The starting point is the TypeClassesSpec.scala file. Just uncomment the spec and get started.

The goal of the project is to use type classes to implement common functional programming abstractions. You will learn about type classes, Functors and Monads.

After completing the TypeClassesSpec, enable the LawSpec to check your implementation against the laws of the type classes. Test cases are generated by discipline.

Quick start:

sbt "~functional-type-classes/test"

Kata 6 - Simple dependency injection

The point of this Kata is to explore a functional datastructure, that may be readily used for a very simple but versatile form of dependency injection.

Your starting point is the spec for said construct, namely ReaderSpec file.

Your goal is to use this spec as guide to implement the datastructure called Reader.

Kata _ - Reactive Streams with akka-streams

The starting point is the AkkaStreamKata1Spec.scala file. Just uncomment the spec and get started.

The goal of the project is to familiarize yourself with Sinks, Sources and Flows to learn the basis of akka streams.

Quick start:

sbt "~reactive-streams-with-akka/test"