book

JavaScript

by T. J. Crowder

July 2020

Intermediate to advanced

608 pages

15h 43m

English

Wrox

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WHAT DOES THIS BOOK COVER?WHO SHOULD READ THIS BOOKHOW TO USE THIS BOOKHOW TO CONTACT THE AUTHOR
DEFINITIONS, WHO'S WHO, AND TERMINOLOGYWHAT ARE THE “NEW TOYS”?HOW DO NEW TOYS GET CREATED?KEEPING UP WITH THE NEW TOYSUSING TODAY'S TOYS IN YESTERDAY'S ENVIRONMENTS, AND TOMORROW'S TOYS TODAYREVIEWNOTES
AN INTRODUCTION TO LET AND CONSTTRUE BLOCK SCOPEREPEATED DECLARATIONS ARE AN ERRORHOISTING AND THE TEMPORAL DEAD ZONEA NEW KIND OF GLOBALCONST: CONSTANTS FOR JAVASCRIPTBLOCK SCOPE IN LOOPSOLD HABITS TO NEWNOTE
ARROW FUNCTIONS AND LEXICAL THIS, SUPER, ETC.DEFAULT PARAMETER VALUES“REST” PARAMETERSTRAILING COMMAS IN PARAMETER LISTS AND FUNCTION CALLSTHE FUNCTION NAME PROPERTYFUNCTION DECLARATIONS IN BLOCKSOLD HABITS TO NEW
WHAT IS A CLASS?INTRODUCING THE NEW CLASS SYNTAXCOMPARING WITH THE OLDER SYNTAXCREATING SUBCLASSESLEAVING OFF OBJECT.PROTOTYPENEW.TARGETCLASS DECLARATIONS VS. CLASS EXPRESSIONSMORE TO COMEOLD HABITS TO NEWNOTES
COMPUTED PROPERTY NAMESSHORTHAND PROPERTIESGETTING AND SETTING AN OBJECT'S PROTOTYPEMETHOD SYNTAX, AND SUPER OUTSIDE CLASSESSYMBOLNEW OBJECT FUNCTIONSSYMBOL.TOPRIMITIVEPROPERTY ORDERPROPERTY SPREAD SYNTAXOLD HABITS TO NEWNOTES
ITERATORS, ITERABLES, THE FOR-OF LOOP, AND ITERABLE SPREAD SYNTAXGENERATOR FUNCTIONSOLD HABITS TO NEWNOTES
OVERVIEWBASIC OBJECT DESTRUCTURINGBASIC ARRAY (AND ITERABLE) DESTRUCTURINGDEFAULTSREST SYNTAX IN DESTRUCTURING PATTERNSUSING DIFFERENT NAMESCOMPUTED PROPERTY NAMESNESTED DESTRUCTURINGPARAMETER DESTRUCTURINGDESTRUCTURING IN LOOPSOLD HABITS TO NEWNOTES
WHY PROMISES?PROMISE FUNDAMENTALSUSING AN EXISTING PROMISEADDING HANDLERS TO ALREADY SETTLED PROMISESCREATING PROMISESOTHER PROMISE UTILITY METHODSPROMISE PATTERNSPROMISE ANTI-PATTERNSPROMISE SUBCLASSESOLD HABITS TO NEWNOTES

ASYNC FUNCTIONSASYNC ITERATORS, ITERABLES, AND GENERATORSOLD HABITS TO NEWNOTES
TEMPLATE LITERALSIMPROVED UNICODE SUPPORTITERATIONNEW STRING METHODSUPDATES TO THE MATCH, SPLIT, SEARCH, AND REPLACE METHODSOLD HABITS TO NEWNOTES
NEW ARRAY METHODSITERATION, SPREAD, DESTRUCTURINGSTABLE ARRAY SORTTYPED ARRAYSOLD HABITS TO NEWNOTES
MAPSSETSWEAKMAPSWEAKSETSOLD HABITS TO NEWNOTES
INTRODUCTION TO MODULESMODULE FUNDAMENTALSRENAMING EXPORTSRE-EXPORTING EXPORTS FROM ANOTHER MODULERENAMING IMPORTSIMPORTING A MODULE'S NAMESPACE OBJECTEXPORTING ANOTHER MODULE'S NAMESPACE OBJECTIMPORTING A MODULE JUST FOR SIDE EFFECTSIMPORT AND EXPORT ENTRIESIMPORTS ARE LIVE AND READ-ONLYMODULE INSTANCES ARE REALM-SPECIFICHOW MODULES ARE LOADEDIMPORT/EXPORT SYNTAX REVIEWDYNAMIC IMPORTTREE SHAKINGBUNDLINGIMPORT METADATAWORKER MODULESOLD HABITS TO NEW
REFLECTPROXYOLD HABITS TO NEWNOTES
THE FLAGS PROPERTYNEW FLAGSNAMED CAPTURE GROUPSLOOKBEHIND ASSERTIONSUNICODE FEATURESOLD HABITS TO NEWNOTES
INTRODUCTIONHERE THERE BE DRAGONS!BROWSER SUPPORTSHARED MEMORY BASICSMEMORY IS SHARED, NOT OBJECTSRACE CONDITIONS, OUT-OF-ORDER STORES, STALE VALUES, TEARING, AND MORETHE ATOMICS OBJECTSHARED MEMORY EXAMPLEHERE THERE BE DRAGONS! (AGAIN)OLD HABITS TO NEWNOTES
BIGINTNEW INTEGER LITERALSNEW MATH METHODSEXPONENTIATION OPERATOR (**)DATE.PROTOTYPE.TOSTRING CHANGEFUNCTION.PROTOTYPE.TOSTRING CHANGENUMBER ADDITIONSSYMBOL.ISCONCATSPREADABLEVARIOUS SYNTAX TWEAKSVARIOUS STANDARD LIBRARY / GLOBAL ADDITIONSANNEX B: BROWSER-ONLY FEATURESTAIL CALL OPTIMIZATIONOLD HABITS TO NEWNOTES
PUBLIC AND PRIVATE CLASS FIELDS, METHODS, AND ACCESSORSOLD HABITS TO NEWNOTES
TOP-LEVEL AWAITWEAKREFS AND CLEANUP CALLBACKSREGEXP MATCH INDICESSTRING.PROTOTYPE.REPLACEALLATOMICS ASYNCWAITVARIOUS SYNTAX TWEAKSLEGACY DEPRECATED REGEXP FEATURESTHANK YOU FOR READING!NOTES
FEATURES IN ALPHABETICAL ORDERNEW FUNDAMENTALSNEW SYNTAX, KEYWORDS, OPERATORS, LOOPS, AND SIMILARNEW LITERAL FORMSSTANDARD LIBRARY ADDITIONS AND CHANGESMISCELLANEOUS

Content preview from JavaScript

INTRODUCTION

THIS BOOK IS FOR ANY JAVASCRIPT (OR TYPESCRIPT) programmer who wants to get up to speed on the latest features added to JavaScript in the last few years, and who wants to know how to stay informed as the language continues to evolve and grow. You can find nearly all of the information in this book somewhere on the web if you look hard enough and you’re cautious about what sites you trust; this book provides all of the technical details in one place, along with showing you how to keep track of the changes as they continue to be made. You can continue to stay up-to-date via the book's website at https://thenewtoys.dev, where I continue covering new features as they're added.

WHAT DOES THIS BOOK COVER?

Here's a glance at what's in each chapter:

Chapter 1: The New Toys in ES2015–ES2020, and Beyond — begins with introducing various players in the JavaScript world and some important terminology. Then it describes the definition of “The New Toys” for the purposes of the book; covers the way new features are added to JavaScript, how that process is managed, and by whom; and explains how to follow and participate in that process. It finishes by introducing some tools for using the new toys in older environments (or using the very newest toys in current environments).
Chapter 2: Block-Scoped Declarations: let and const — covers the new declaration keywords let and const and the new scoping concepts they support, including in-depth coverage of scoping in loops, particularly ...