functional programming

2/2- Preparing for Scala 3

During the last episode, we built a structure called Vect whose size is encoded in the type. There were some shortcomings however, which we will fix in this article. The goal still being to write, a zip function whose calls compile only with Vect of the same size. A pinch

scala

3/n - How do I in FP... trying several input for the same function

In the previous entry of this series, I wrote about error recovery in a functional way. But sometimes, we want to try several inputs until we retrieve (optionally) a result. This is the case if you have a function which compute a location from a string (think geo-search), and which

conference

3/3 An Autumn of conferences: Scala.io

For the third year in a row, I was attending Scala.io in Lyon at the end of October. Like in 2018, the conference spanned on 3 days, the first one being dedicated to workshops. I only had a ticket for the 2 days of talks. As always, this conference

conference

2/3 An Autumn of conferences: Lambda World Cadiz

Two weeks after the Devfest Toulouse, I was in Cádiz to attend 𝛌World. It is a conference focused on Functional Programming. It was composed of two days, one mostly dedicated to workshops while the second one was only about talks. For my first time there, the least I can say

scala

2/n - How do I ... in FP: selective recovery on error

Problem setup: Let's say we have this ADT to model some errors sealed abstract class AppError extends Product with Serializable object AppError{ case class ParseError(msg: String, field: String) extends AppError case class GeneralError(msg: String) extends AppError case class MissingValueError(name: String) extends AppError } And some existing method: def

scala

Tagless Final Memo (in Scala)

Sometimes, the typeclass syntax in Scala can be confusing. Here is a simple memo to quickly remember how it is encoded in Scala 2.

functional programming

Scala.io 2018

In the end of October 2018, in Lyon, the Scala.io conference took place. I was there and in this article are sumed up my notes and memories from this event. It is not an easy task to sumarize every presentation I went to, so instead of trying to do

functional programming

1/n - How do I ... in FP : Validation

Here is a small post-it like article. Just to remember some useful patterns we hit in everyday life as software developers. This post is the first in a (potentially infinite) stream. How do I validate things The case The basic. Let say we are in a web app exposing a

recursion

Skiing in Singapore - Episode 1

About 4 months ago, a friend of mine sent me a link to this fun challenge proposed by Redmart. The goal is to find not the shortest but the longest path in a mountain. It is a perfect exercise to dive into some functional code and apprehend recursion for new