Table Of ContentJavaScript-mancy: Object-Oriented
Programming
Mastering the Arcane Art of Summoning Objects in
JavaScript for C# Developers
Jaime González García
This book is for sale at http://leanpub.com/javascript-mancy-object-oriented-
programming
This version was published on 2017-09-15
* * * * *
This is a Leanpub book. Leanpub empowers authors and publishers with the Lean
Publishing process. Lean Publishing is the act of publishing an in-progress ebook
using lightweight tools and many iterations to get reader feedback, pivot until you
have the right book and build traction once you do.
* * * * *
© 2016 - 2017 Jaime González García
ISBN for EPUB version: 978-1976459238
ISBN for MOBI version: 978-1976459238
To my beautiful wife Malin and my beloved son Teo
Table of Contents
About The Author
About the Technical Reviewers
Prelude
A Note to the Illustrious Readers of JavaScript-mancy: Getting Started
A Story About Why I Wrote This Book
Why Should You Care About JavaScript?
What is the Goal of This Book?
What is the Goal of The JavaScript-mancy Series?
Why JavaScript-mancy?
Is This Book For You?
How is The Book Organized?
How Are The JavaScript-mancy Series Organized? What is There in the Rest of the
Books?
Understanding the Code Samples in This Book
A Note About ECMAScript 5 (ES5) and ES6, ES7, ES8 and ESnext within The Book
A Note Regarding the Use of var, let and const
A Note About the Use of Generalizations in This Book
Do You Have Any Feedback? Found Any Error?
A Final Word From the Author
Once Upon a Time…
Tome II. JavaScriptmancy and OOP: The Path of The
Summoner
Introduction to the Path of Summoning and Commanding Objects (aka OOP)
Let me Tell You About OOP in JavaScript
C# Classes in JavaScript
OOP Beyond Classes
Combining Classes with Object Composition
The Path of the Object Summoner Step by Step
Concluding
Summoning Fundamentals: Encapsulation and Information Hiding
Let’s get Started With The Basics of OOP!
Encapsulation: Creating Objects in JavaScript
Object Initializers
Constructor Functions and the New Operator
Data Hiding in JavaScript
Object Initializers vs Constructor Functions
Object Factories vs Constructor Functions
Concluding
Exercises
Summoning Fundamentals: Prototypical Inheritance
You Don’t Repeat Yourself. Inheritance!
Classical Inheritance vs Prototypical Inheritance
JavaScript Prototypical Inheritance
Object Prototypes
Object Prototypes with Object.Create or OLOO
Defining Prototypes with Constructor Functions
Creating Longer Prototype Chains
What About Concatenative Protypical Inheritance?
Object Initializers vs Object.create vs Constructor Functions
Concluding
Exercises
Summoning Fundamentals: Polymorphism
Polymorphism Means Many Forms
Polymorphism in C#
Polymorphism in JavaScript
Concluding
Exercises
White Tower Summoning: Mimicking C# Classical Inheritance in JavaScript
Ever Heard of Classical Inheritance?
Emulating a C# Class in JavaScript
Constructor Function + Prototype = Class
Mimicking Classical Inheritance in JavaScript
Simplifying Classical Inheritance in ES5
Concluding
Exercises
White Tower Summoning Enhanced: The Marvels of ES6 Classes
Create These Units Faster with ES6 Classes!
From ES5 “Classes” to ES6 Classes
Prototypical Inheritance via Extends
Overriding Methods in ES6 Classes
Static Members and Methods
ES6 Classes and Information Hiding
ES6 Classes Behind the Curtain
Concluding
Exercises
Black Tower Summoning: Objects Interweaving Objects with Mixins
The Problem With Classes and Classical Inheritance…
Free Yourself From Classes With Object Composition and Mixins
Limitations of Mixins as Objects
Functional Mixins
Combining Mixins with ES6 Classes
Object.assign in Depth
Object.assign Alternatives for ES5 JavaScript-mancers
Concluding
Exercises
Black Tower Summoning: Safer Object Composition with Traits
An Improvement Over Mixins
Traits
Traits with traits.js
Composing Traits
What Happens When You Miss Required Properties?
Resolving Name Conflicts
Traits and Data Privacy
High Integrity Objects With Immutable Traits
Traits vs Mixins
Concluding
Exercises
Black Tower Summoning: Next Level Object Composition With Stamps
I Call Them Stamps
What are Stamps?
Stamps OOP Embraces JavaScript
Stamps By Example
Stamp Composition
Stamp Fluent API
Concluding: Stamps vs Mixins vs Traits
Exercises
Object Internals: The Secrets of Objects
A Nifty Trick… Object Internals
All your Objects Are Belong to Object
Defining Properties with Object.defineProperty
Defining Multiple Properties with Object.defineProperties
Beautiful Property Manipulation with ESnext Decorators
Class And Method Decorators
Create Objects With Object.create And Property Descriptors
Metaprogramming
Other Useful Object Methods
Concluding
Exercises
More Metaprogramming with Reflect, Proxies and Symbols
How Good Are You at Reflection?
ES6 Reflect
Reflection? What is reflection?
ES6 Proxies
ES6 Symbols and Meta-programming
Concluding
Exercises
TypeScript
You Shall Only Use Types!
JavaScript + Types = Awesome Dev Productivity
Any JavaScript is Valid TypeScript
So, What Are The Advantages and Disadvantages of TypeScript?
Setting up a Simple TypeScript project
Cool TypeScript Features
Type Annotations In TypeScript
Working with TypeScript in Real World Applications
Concluding
Exercises
Tome II. Epilogue
Thank you!
References and Appendix
Appendix A. On the Art of Summoning Servants and Critters, Or
Understanding The Basics of JavaScript Objects
An Army of Objects
Object Initializers (a.k.a. Object Literals)
Creating Objects With Factories
Data Privacy in JavaScript
ES6 Improves Object Initializers
ES6 Symbols and Data Privacy
Concluding
Exercises
Appendix B. Mysteries of the JavaScript Arcana: JavaScript Quirks
Demystified
A Couple of Tips About JavaScript Quirks and Gotchas
A Quick Refresher of the JavaScript Arcana 101
This, Your Most Dangerous Foe
Global Scope by Default and Namespacing in JavaScript
Type Coercion Madness
Using JavaScript in Strict Mode
Concluding
Exercises
Appendix C. More Useful Function Patterns: Function Overloading
Have you Heard About The Marvels Of Overloading?
The Problem with Function Overloading in JavaScript
How Do We Do Function Overloading Then?
Function Overloading by Inspecting Arguments
Using an Options Object
Relying on ES6 Defaults
Taking Advantage of Polymorphic Functions
Concluding
Exercises
Appendix D. Setting Up Your Developing Environment For ES6
Using ES6 with Node.js
ES6 and Modern Browsers
Real-World ES6 Development Environments
Appendix E. Fantasy Glossary
References
Specifications
Books
White papers
Articles
Notes
About The Author
Jaime González García
Jaime González García (@Vintharas) Software Developer and UX guy, speaker,
author & nerd
Jaime is a full stack web developer and UX designer who thinks it’s weird to write
about himself in the third person. During the past few years of his career he has been
slowly but surely specializing in front-end development and user experience, and
somewhere and some time along the way he fell in love with JavaScript. He still
enjoys developing in the full stack though, bringing ideas to life, building things
from nothingness, beautiful things that are a pleasure and a delight to use.
Jaime works as a Technical Solutions Consultant at Google helping publishers be
great. He spends part of his time as a Developer Relations for Angular and Google in
the Nordics developer community. He speaks at conferences, writes articles, runs
workshops and talks to developers and companies about how they can do cool things
with Angular and JavaScript. He also arranges developer community events at the
Google Office in Stockholm as a way to support and encourage the thriving local dev
ecosystem and put it in contact with other Googlers.
In his spare time he builds his own products and blogs at barbarianmeetscoding.com
(long story that one). He loves spending time with his beloved wife Malin and son
