functional-programming.md

Functional Programming

• The Little Idea of Functional Programming
  http://jaysoo.ca/2016/01/13/functional-programming-little-ideas/
  Describes the three basic principles of FP: "data in/data out", "code as data", and "function composition" all the way down, and demonstrates transforming some data. Has some very helpful graphics and illustrations.

• Understanding Programmatic Side Effects
  https://web.archive.org/web/20160326014453/http://web24studios.com/2015/10/understanding-programmatic-side-effects/
  A short article that explains the concept of "side effects"

• What Is Functional Programming?
  http://blog.jenkster.com/2015/12/what-is-functional-programming.html
  Describes how side effects and "hidden inputs" add complexity to code, in very clear terms.

• Getting Functional with Javascript
  http://www.datchley.name/getting-functional-with-javascript-part-1/
  http://www.datchley.name/getting-functional-with-javascript-part-2/
  http://www.datchley.name/getting-functional-with-javascript-part-3/
  Demonstrates FP concepts by showing how to filter, group, and sort an array of data. Lots of good descriptions, samples, and explanations.

• Functional Programming for Javascript People
  https://medium.com/@chetcorcos/functional-programming-for-javascript-people-1915d8775504
  Tries to explain core FP concepts and patterns in understandable terms.

• Functors, Applicatives, and Monads in Pictures
  http://adit.io/posts/2013-04-17-functors,_applicatives,_and_monads_in_pictures.html
  A long article that tries to describe several FP terms using lots of cartoons.

• Introduction to Immutable.js and Functional Programming Concepts
  https://auth0.com/blog/2016/03/23/intro-to-immutable-js/
  Covers the benefits of using immutable data, pure functions, and other FP concepts, and how those related to Immutable.js.

• Practical Intro to Monads in Javascript
  http://tech.evojam.com/2016/02/22/practical-intro-to-monads-in-javascript/
  http://tech.evojam.com/2016/03/21/practical-intro-to-monads-in-javascript-either/
  An attempt to describe monads aimed at developers and engineers.

• A Gentle Introduction to Functional Javascript
  http://jrsinclair.com/articles/2016/gentle-introduction-to-functional-javascript-intro/
  http://jrsinclair.com/articles/2016/gentle-introduction-to-functional-javascript-arrays/
  http://jrsinclair.com/articles/2016/gentle-introduction-to-functional-javascript-functions/
  http://jrsinclair.com/articles/2016/gentle-introduction-to-functional-javascript-style/
  Goes through a number of FP-related aspects in Javascript.

• Professor Frisby's Mostly Adequate Guide to Functional Programming
  https://drboolean.gitbooks.io/mostly-adequate-guide/content/
  A long (and still growing) online book covering functional topics. Starts fairly simple, definitely gets more complex in later chapters.

• Functional Thinking
  http://nealford.com/functionalthinking.html
  An extended series of articles collected together. Aimed at Java/JVM programmers, and makes a number of comparisons of OOP vs FP.

• Functional Programing in Javascript
  http://reactivex.io/learnrx/
  Teaches functional programming concepts through a series of interactive exercises. Intended as a precursor to learning the Reactive Extensions for Javascript library (RxJS), but uses plain JS and teaches general concepts in the process. (Later exercises are hidden until earlier ones are completed - hit "Show Answer" and "Run" on an exercise if you want to skip ahead).

• The "Thinking Functionally" series
  http://fsharpforfunandprofit.com/series/thinking-functionally.html
  A series of lessons teaching functional concepts using F#. Very well written, clear and easy to understand. Examples use F#, but concepts are widely applicable.

• Imperative to Functional Programming Succinctly
  https://www.syncfusion.com/resources/techportal/details/ebooks/imperative
  A short ebook covering many functional concepts.

• Functional Programming in Javascript
  https://www.youtube.com/watch?v=BMUiFMZr7vk&list=PL0zVEGEvSaeEd9hlmCXrk5yUyqUag-n84
  A web series by a quirky programmer showing you high level functional concepts in Javascript

• Functional Programming Jargon
  https://github.com/hemanth/functional-programming-jargon
  A list of FP terms with easier-to-understand definitions and explanations.

• An Introduction to Reasonably Pure Functional Programming
  https://www.sitepoint.com/an-introduction-to-reasonably-pure-functional-programming/
  Explain four key concepts of functional programming: pure functions, immutable values, composition, and side effects

• Functors, Applicatives, and Monads in Plain English
  http://www.russbishop.net/monoids-monads-and-functors
  An attempt to explain these concepts in reasonable terms.

• Learning Functional Programming with Javascript
  https://youtu.be/e-5obm1G_FY
  A great talk by Anjana Vakil. Covers several basic concepts of functional programming, including some very nice examples of map/filter/reducer, a clear fdefinition of side effects, and an explanation of how specialized immutable data libraries work.

• Thinking in Ramda
  http://randycoulman.com/blog/categories/thinking-in-ramda/
  A series of articles digging into techniques to use with the Ramda FP utility library

• Functional Programming Isn't the Answer
  http://degoes.net/articles/fp-is-not-the-answer
  A reminder that while FP has potential benefits, it's ultimately just a tool, and the end goal is useful software.

• An Intro to Functional Programming Concepts in Javascript
  https://medium.com/@collardeau/intro-to-functional-programming-concepts-in-javascript-b0650773139c
  https://medium.com/@collardeau/intro-to-functional-programming-concepts-in-javascript-part-2-f45228c49eed
  https://medium.com/@collardeau/part-3-an-intro-to-functional-programming-concepts-in-javascript-febf9368ffe6
  A multi-part series covering a number of FP concepts, how to use them in Javascript, and use of the Ramda FP utility library

• JavaScript and Functional Programming
  https://bethallchurch.github.io/JavaScript-and-Functional-Programming/
  An overview of the basic principles of functional programming, and how they can be applied in Javascript. Also includes links to a variety of other articles and resources.

• Functional-Light JS
  https://github.com/getify/Functional-Light-JS
  This book explores the core principles of functional programming (FP) that can be applied to JavaScript. But what makes this book different is that we approach these principles without drowning in all the heavy terminology. We look at a subset of FP foundational concepts that I call "Functional-Light Programming" (FLP) and apply it to JavaScript.

• The Case for Lenses in Pragmatic Business Applications
  http://www.brandonkeown.com/2016/10/lenses-for-fun-and-profit.html
  Demonstrates the use of Ramda's "lens" concept for encapsulating data access

• Functional Lenses, How Do They Work
  https://medium.com/@dtipson/functional-lenses-d1aba9e52254
  A dive into the "lens" concept, and how they can be used to manipulate data structures

• Don't Be Scared of Functional Programming
  https://www.smashingmagazine.com/2014/07/dont-be-scared-of-functional-programming/
  Several examples of functional programming principles, both in plain JS and with Underscore.js

• Functional Programming Basics in ES6
  https://www.youtube.com/watch?v=HvMemAgOw6I
  Talk on functional programming with JavaScript and ES6 syntax. Covers basics such as purity, referential transparency, closures, immutability, currying, composition, and recursion.

• Using Composition and Array Functions
  http://ignaciochavez.com/using-composition-and-array-functions/
  Some useful examples of composing together different functions to accomplish a task. Has some very nice diagrams illustrating the process.

• Dipping a toe into functional JS with lodash/fp
  https://simonsmith.io/dipping-a-toe-into-functional-js-with-lodash-fp/
  Examples of using Lodash's functional API for logic and React component composition

• Composability: From Callbacks to Categories in ES6
  https://medium.com/@homam/composability-from-callbacks-to-categories-in-es6-f3d91e62451e
  Explores different solutions to "callback hell", based on various FP concepts

• So You Want To Be a Functional Programmer
  https://medium.com/@cscalfani/so-you-want-to-be-a-functional-programmer-part-6-db502830403
  A multi-part series on functional programming concepts and learning approaches (links to previous parts in the article).

• Imperative vs Declarative Programming
  https://medium.freecodecamp.com/imperative-vs-declarative-programming-283e96bf8aea
  Metaphors, examples, and explanations for the terms "declarative" and "imperative", and how those relate to Functional Programming

• Higher-order functions in Lodash
  http://pragmatists.pl/blog/2017/05/higher-order-functions-in-lodash/
  An explanation of several FP concepts like partial application and currying, and how Lodash offers utility functions to help make use of those concepts.

• How to Draw an Owl
  https://glebbahmutov.com/blog/how-to-draw-an-owl/
  Demonstrates refactoring some complex imperative code into a functional approach that uses concepts like pure functions, lenses, immutable data, and the Maybe monad

• Classes, Complexity, and Functional Programming
  https://medium.com/@kentcdodds/classes-complexity-and-functional-programming-a8dd86903747
  Kent C Dodds looks at pros and cons of using classes, issues with the this keyword in Javascript, and some ways to avoid using classes

• What's Functional Programming All About?
  http://www.lihaoyi.com/post/WhatsFunctionalProgrammingAllAbout.html
  A detailed explanation of how "functional" programming differs from "imperative" programming, using a food recipe as an example of the steps involved.

• Higher Order Functions and Redux Thunk
  https://medium.com/@joedski/higher-order-functions-and-redux-thunk-1e5983ae6b03
  An exploration of ways to wrap behavior around thunks, including composing functions together.