Functional Programming in javascript How to improve your javascript programs using functional techniques

274 Pages·2016·14.64 MB·English

by  Luis Atencio

Functional Programming in JavaScript

Functional
Programming
in JavaScript
LUIS ATENCIO
MANNING
SHELTER ISLAND
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To my wonderful wife, Ana.
Thank you for your unconditional support
and for being the source of passion and inspiration in my life.

brief contents
PART 1 THINK FUNCTIONALLY ..................................................1
1 ■ Becoming functional 3
2 ■ Higher-order JavaScript 23
PART 2 GET FUNCTIONAL........................................................55
3 ■ Few data structures, many operations 57
4 ■ Toward modular, reusable code 84
5 ■ Design patterns against complexity 117
PART 3 ENHANCING YOUR FUNCTIONAL SKILLS......................151
6 ■ Bulletproofing your code 153
7 ■ Functional optimizations 180
8 ■ Managing asynchronous events and data 205
vii

contents
preface xv
acknowledgments xvii
about this book xix
PART 1 THINK FUNCTIONALLY.......................................1
1 Becoming functional 3
1.1 Can functional programming help? 5
1.2 What is functional programming? 5
Functional programming is declarative 7 ■ Pure functions and
the problem with side effects 9 ■ Referential transparency and
substitutability 13 ■ Preserving immutable data 15
1.3 Benefits of functional programming 16
Encouraging the decomposition of complex tasks 16
Processing data using fluent chains 18 ■ Reacting to the
complexity of asynchronous applications 19
1.4 Summary 22
ix