Optics By Example
Optics By Example
Optics By Example

Last updated on 2019-12-09

About the Book

Hi! I'm Chris, I'm writing a book on optics and lenses called Optics By Example

Optics By Example is a one-stop comprehensive guide to learning and mastering optics in functional programming languages. It covers what optics are, how to use existing combinators, and how to write your own custom optics. Each topic is accompanied by copious examples and exercises!


Optics have become a wonderful and powerful new way of working with immutable data structures. They're almost a necessity at this point; and the benefits they bring in terms of re-usability, simplification of code maintenance & refactoring, and expressivity are immense! However, learning to use optics can be tricky or even intimidating at first, it's not always clear how to build up a large complicated mutation or query from the building blocks of optics. Optics by example is here to help!

This book is great as a first guide to optics, as a reference guide for discovering and mastering the optics you need for day-to-day problems, and as a springboard into new optics, and ideas which you might not have even heard of.

About the Author

Chris Penner
Chris Penner

Hey there! I'm a programmer, coffee lover and acrobat!

I love functional programming and I love writing, seems only natural to bring the two together (especially since it's a bit tougher to match coding and acrobatics!)

Hope you enjoy my book!

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