You likely use it every day at work.
This makes it possible to practice and apply your acquired knowledge each day on real world programs rather than pet projects on nights and weekends in an esoteric FP language.
We don't have to learn everything up front to start writing programs.
In a pure functional language, you cannot log a variable or read a DOM node without using monads. Here we can cheat a little as we learn to purify our codebase. It's also easier to get started in this language since it's mixed paradigm and you can fall back on your current practices while there are gaps in your knowledge.
The language is fully capable of writing top notch functional code.
bind all over the place lest
this change out from under us, we have various work arounds for the quirky behavior when the
new keyword is forgotten, private members are only available via closures. To a lot of us, FP feels more natural anyways.
For a best reading experience, read it online via Gitbook.
To make the training efficient and not get too bored while I am telling you another story, make sure to play around with the concepts introduced in this book. Some can be tricky to catch at first and are better understood by getting your hands dirty. All functions and algebraic data-structures presented in the book are gathered in the appendixes. The corresponding code is also available as an npm module:
$ npm i @mostly-adequate/support
Alternatively, exercises of each chapter are runnable and can be completed in your editor! For example, complete the
exercises/ch04 and then run:
$ npm run ch04
git clone https://github.com/MostlyAdequate/mostly-adequate-guide.gitcd mostly-adequate-guide/npm installnpm run setupnpm run generate-pdfnpm run generate-epub
Note! To generate the ebook version you will need to install
ebook-convert. Installation instructions.
Part 1 (chapters 1-7) is a guide to the basics. I'm updating as I find errors since this is the initial draft. Feel free to help!
Part 2 (chapters 8-13) address type classes like functors and monads all the way through to traversable. I hope to squeeze in transformers and a pure application.
Part 3 (chapters 14+) will start to dance the fine line between practical programming and academic absurdity. We'll look at comonads, f-algebras, free monads, yoneda, and other categorical constructs.
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