Free Monads: from the basics to the implementation of composable and effectful stream processing

In the previous post, we introduced IdrisPipes, a library for composable and effectful production, transformation and consumption of streams of data in Idris. We talked about the motivations behind this library, its API and its model, and some of the features it offers. In this post, we will embark in a journey from the basics... Continue Reading →

Monoids: what they are, why they are useful, and what they teach us about software

Monoids are a pretty interesting concept in software development. Monoids are everywhere. Monoids are simple yet powerful. And Monoids have a lot to teach us about software, in particular about composition and building powerful abstraction. This post will take you through a small tour of what Monoids are and are for. We will first define... Continue Reading →

How the List Monad helped me better understand Non-deterministic Polynomial time complexity

I have always been puzzled with the definition of NP: Non-deterministic Polynomial time complexity. A problem is in NP if it can be solved by an algorithm that runs in polynomial time on a non-deterministic Turing Machine, a computer that can "guess" which path to take toward the right answer when given a choice. I... Continue Reading →

A study of 4 Money class designs, featuring Martin Fowler, Kent Beck and Ward Cunningham implementations.

Following a TDD training that could have gone better, I started to read the Test Driven Development: by example book (by Kent Beck). It offers a perspective on TDD that is far from being dogmatic. It is a really good back and I highly encourage you to read it. But this post is not about... Continue Reading →

Hexagonal Architecture and Free Monad: Two related design patterns?

Disclaimer: You do not need to understand Monads to follow this post. This is not a Monad tutorial either, but it might help you getting some intuition on what is a Monad. Some knowledge of Haskell and C++ might help but are not pre-requisite.   There is a lot of talk about Domain Driven Design... Continue Reading →

10 things Idris improved over Haskell

The 1.0.0 of Idris has been released just a few months back, just enough to start trying out the language and some of the possibilities dependent typing offers. But this post is not about dependent typing. There is already a really good book that came out this year, named Type Driven Development with Idris, exploring... Continue Reading →

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