Functional Programming in JavaScript

274 Pages·2016·3.331 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
P 1 T .......................................1
ART HINK FUNCTIONALLY
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