Effective JavaScript

Your Constructors new-Agnostic 89 Item 34: Store Methods on Prototypes 92 Item 35: Use Closures to Store Private Data 94 Item 36: Store Instance State Only on Instance Objects 95 Item 37: Recognize the Implicit Binding of this 98 Item 38: Call Superclass Constructors from Subclass Constructors 101 Item 39: Never Reuse Superclass Property Names 105 Item 40: Avoid Inheriting from Standard Classes 106 Item 41: Treat Prototypes As an Implementation Detail 109 Item 42: Avoid Reckless Monkey-Patching 110 Chapter 5: Arrays and Dictionaries 113 Item 43: Build Lightweight Dictionaries from Direct Instances of Object 113 Item 44: Use null Prototypes to Prevent Prototype Pollution 116 Item 45: Use hasOwnProperty to Protect Against Prototype Pollution 118 Item 46: Prefer Arrays to Dictionaries for Ordered Collections 123 Item 47: Never Add Enumerable Properties to Object.prototype 125 Item 48: Avoid Modifying an Object during Enumeration 127 Item 49: Prefer for Loops to for...in Loops for Array Iteration 132 Item 50: Prefer Iteration Methods to Loops 133 Item 51: Reuse Generic Array Methods on Array-Like Objects 138 Item 52: Prefer Array Literals to the Array Constructor 140 Chapter 6: Library and API Design 143 Item 53: Maintain Consistent Conventions 143 Item 54: Treat undefined As "No Value" 144 Item 55: Accept Options Objects for Keyword Arguments 149 Item 56: Avoid Unnecessary State 153 Item 57: Use Structural Typing for Flexible Interfaces 156 Item 58: Distinguish between Array and Array-Like 160 Item 59: Avoid Excessive Coercion 164 Item 60: Support Method Chaining 167 Chapter 7: Concurrency 171 Item 61: Don't Block the Event Queue on I/O 172 Item 62: Use Nested or Named Callbacks for Asynchronous Sequencing 175 Item 63: Be Aware of Dropped Errors 179 Item 64: Use Recursion for Asynchronous Loops 183 Item 65: Don't Block the Event Queue on Computation 186 Item 66: Use a Counter to Perform Concurrent Operations 190 Item 67: Never Call Asynchronous Callbacks Synchronously 194 Item 68: Use Promises for Cleaner Asynchronous Logic 197 Index 201

is hard-won experience distilled into a guided tour. It's one of the few books on JavaScript that I'll recommend without hesitation." -Alex Russell, TC39 member, software engineer, Google "Rarely does anyone have the opportunity to study alongside a master in their craft. This book is just that-the JavaScript equivalent of a time-traveling philosopher visiting fifth century BC to study with Plato." -Rick Waldron, JavaScript evangelist, Bocoup