This article is part of the Scala knowledge bits Series.
Periodically, I will publish new exercises so you can slowly build up knowledge about Scala.
It is designed to be done in a very short amount of time and learn a little bit each day, just to create a routine.
This episode will teach you about Scala
Hope you are going to enjoy it! It is designed for anyone to learn Scala from scratch and slowly learn, one Bit at a time.
After this Bit, I would love to hear your feedback in the comments down below.
Feel free to join the Discord server as well if you would like some help and support from the rest of our community.
What are we learning today?
Today we are going to learn about Scala
Either, you will see, is kind of a in-between
Try to experiment to see the similarity and differences.
Time to try on the exercise on your own and scroll down for more information when you are done or if you are stuck.
Here is an exercise to complete today.
If I did my job well, you should be able to guess by yourself the solution based on what you previously learned and based on the clues.
But if you get stuck, scroll down to get more information.
The goal of the exercise is to replace the
??? by a piece of code so that the exercise compiles and that’s how you win! Good luck!
You can fill the exercise right in here:
Or, if it does not load, go on to Scastie (bzjEzMzhQmSOiJm2bejFkw).
More information about Scala
In this exercise you will learn (or have learned, if you have already solved the puzzle) about Scala
Option, you can create
Either in two ways:
Rightwhich would be similar to
Leftwhich, over time, became similar to
None, except you can store information. I am saying “over time” because up until Scala v2.12+,
Eitherwas not Right-bias.
Rightwere just two Types. But now,
Leftis accepting to carry error messages and
Rightto be the channel for successes.
You can test which Type is
isRight. You can also use
flatMap, etc… once again. You must be starting to know those functions pretty well by now. This is where the Right-bias come into play.
map will take a function that modify the type contained in
Right and will not do anything if the
Either contains a
If you would like to specifically act on
Right, you can use the
.right methods to project the
Either on one side of the other. For instance, to modify the content of the
Left when it is there, you can do
One major difference with
Try is that
Either will not catch the Exception. If an exception is thrown inside an
Either it will propagate. Inside a
Try it will be captured inside the
Feel free to go back to the exercise, modify the code to try out new things
and get a better intuition for Scala
I hope you have learned something new or had fun during this Scala Knowledge Bit.
Please ask questions or post feedback in the comments below.
Feel free to try on the next Scala Knowledege Bit.
If you are curious about the previous Scala knowledge Bits, go check it out! 🙂