Eckhart Tolle, Guardians of Being: Spiritual Teachings from Our Dogs and Cats alvin October 15, 2019 - 2:20pm

Having lived with many great dogs (and a couple of cats), I just orded this book by Eckhart Tolle. The few pages I can see on the Amazon preview look great. It looks to be more about “mindfulness” and “spirituality” than “religion,” which suits me well. I’m looking forward to it.

A Scala “functional programming style” To-Do List application written with Cats alvin September 7, 2019 - 4:54pm

Back when I was writing Functional Programming, Simplified I started to write a little Scala/FP “To-Do List” application that you can run from the command line, based on a similar application in the Learn You A Haskell For Great Good book. For reasons I don’t remember, I decided not to include it in the book, and forgot about it until I started using GraalVM (“Graal”) recently.

“Shtop Thinking” ~ Guardians of Being (Eckhart Tolle)

There are many nice cartoons/illustrations in Eckhart Tolle’s book Guardians of Being: Spiritual Teachings from Our Dogs and Cats, and this “Shtop Thinking” cartoon is one of my current favorites. (The book is a collaborative effort between Mr. Tolle and Patrick McDonnell, artist/illustrator/cartoonist who may be most well known for his “Mutts” cartoons.)

(Advanced) Scala with Cats alvin July 28, 2018 - 1:06pm

If you’re interested in understanding the Cats library, I’m a big fan of the book, Scala with Cats (formerly known as Advanced Scala with Cats). Noel Welsh and Dave Gurnell have a simple writing style, with good examples. Being an older person, I only wish a print version was available.

Scala: Popular tools, libraries, and frameworks alvin June 15, 2018 - 9:53am
Table of Contents1 - Build tools2 - Testing tools3 - Database4 - Functional Programming5 - Asynchronous/parallel/concurrent programming6 - Web frameworks7 - JSON8 - HTTP clients9 - Configuration/properties10 - Many more

This page is a collection of popular tools, libraries, and frameworks for the Scala programming language.

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Build tools

Type Classes 103: The Cats Library alvin December 19, 2017 - 5:12pm

As a final example of how to use type classes in Scala, I’ll show how to repeat the example from the previous lesson using the open source “Cats” FP library for Scala. With the examples you’ve seen already, this will be a quick process.

Source code

Step 1 is to clone my source code for this lesson, which is available at this URL:

Type Classes 102: The Pizza Class alvin December 19, 2017 - 5:09pm

If you looked at the source code for the Domain Modeling lessons you probably noticed that I said one thing, but did another. I said that I liked the approach of not including any methods in my case classes, but then I wrote this code:

Scala Type Classes 101: Introduction alvin December 19, 2017 - 5:04pm

“A type class is an interface that defines some behavior. More specifically, a type class specifies a bunch of functions, and when we decide to make a type an instance of a type class, we define what those functions mean for that type.”

Learn You a Haskell for Great Good!

Source code

The source code for all of the type class lessons is available at the following URL: