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Functional Structures Refactoring Kata

This refactoring kata aims to let you practice with one of the main functional programming building block: Functional Structures.

The starting code (provided in different languages) implements a use case with an imperative approach. Your mission is to remove every effects (aka computational context) within the applyDiscount function with the power of Functional Structures.

How to use this Kata

The simplest way is to just clone the code and start hacking right away improving the design. The project includes some tests useful to make sure you don't break the code while you refactor.

Proposed Solution

You can take a look at my refactored code (in Scala) wich you will find inside one of the solution-* branchs.

Learning Materials


Is your favorite language missing? Want to contribute? Awesome! Feel free to submit an Issue or a Pull Request.


This project is licensed under the terms of the MIT license.