We are going to cite the definition of a Monoid found on this post:

Conceptually, a monoid is anything that:

- Has a "zero-value": `mempty`, e.g., `0`
- Can be "appended" together: `mappend`, e.g., `+`
- Has an identity with the …

Files and project structure

sbt projects use the same structure as Maven. Creating a project from scratch involve the following steps:

1mkdir some-new-project
2cd some-new-project
3mkdir -p src/{main,test}/{resources,scala}
4mkdir project

Create a …

In this article we are going to use scala to send a message via Telegram. The process is very simple and pretty much involves setting up a bot and making a GET request to Telegram’s api.

The Telegram app on the phone has more features than its …

A fat jar is a jar file that contains any dependencies required by a Java or Scala program. Deployment becomes an easy task if we only have to deal with one single file. In this article we’ll go through the steps required to create a fat jar …

On this article we’re going to set up Metatrader for email sending. This is recommended so you don’t miss important messages happening to your account.

Getting a password from Google

If you want to connect your Google email account, you …

The BatchWriteItem operation allows us to work with groups of up to 25 items per request. Additionally, we can put and delete items to one or multiple tables. Amazon DynamoDB’s page says:

A single call to BatchWriteItem can write up to 16 MB …

A command so important, it deserves its own page:

1git reset --soft HEAD~1

The previous command undoes the last commit to git. I think this is one of those commands that I have typed many times during the last year. It’s very important to know …

Should I use a map or a list? A simple rule:

• If you need to update or remove an item, lists only allow you to do it by index. While maps let you do it by key.

Their simplified representation goes like this:

1{
2  "someMap": {
3 …

This article discusses different approaches for testing classes, services, and PlayFramework controllers using scalatest.

Setting up the project dependencies

First step is to add to build.sbt the next dependency:

1"org.scalatest" %% …

Using case object

Unlike other languages, Scala does not have a keyword for enumerations. One way to implement them is by using case objects. For example:

1sealed trait OperatingSystem extends Product with Serializable
2
3object OperatingSystem {
4 …