JavaScript: The Good Parts

172 Pages·1.49 MB·English

by  Douglas Crockford

JavaScript: The Good Parts
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JavaScript: The Good Parts
Douglas Crockford
Beijing • Cambridge • Farnham • Köln • Sebastopol • Taipei • Tokyo
JavaScript: The Good Parts
by Douglas Crockford
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Table of Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
1. Good Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Why JavaScript? 2
Analyzing JavaScript 3
A Simple Testing Ground 4
2. Grammar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Whitespace 5
Names 6
Numbers 7
Strings 8
Statements 10
Expressions 15
Literals 17
Functions 19
3. Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Object Literals 20
Retrieval 21
Update 22
Reference 22
Prototype 22
Reflection 23
Enumeration 24
Delete 24
Global Abatement 25
vii
4. Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Function Objects 26
Function Literal 27
Invocation 27
Arguments 31
Return 31
Exceptions 32
Augmenting Types 32
Recursion 34
Scope 36
Closure 37
Callbacks 40
Module 40
Cascade 42
Curry 43
Memoization 44
5. Inheritance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Pseudoclassical 47
Object Specifiers 50
Prototypal 50
Functional 52
Parts 55
6. Arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Array Literals 58
Length 59
Delete 60
Enumeration 60
Confusion 61
Methods 62
Dimensions 63
7. Regular Expressions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
An Example 66
Construction 70
Elements 72
viii | Table of Contents