Effective Ruby

Foreword xi Preface xiii Acknowledgments xvii About the Author xix Chapter 1: Accustoming Yourself to Ruby 1 Item 1: Understand What Ruby Considers to Be True 1 Item 2: Treat All Objects as If They Could Be nil 3 Item 3: Avoid Ruby's Cryptic Perlisms 6 Item 4: Be Aware That Constants Are Mutable 9 Item 5: Pay Attention to Run-Time Warnings 12 Chapter 2: Classes, Objects, and Modules 17 Item 6: Know How Ruby Builds Inheritance Hierarchies 17 Item 7: Be Aware of the Different Behaviors of super 24 Item 8: Invoke super When Initializing Subclasses 28 Item 9: Be Alert for Ruby's Most Vexing Parse 31 Item 10: Prefer Struct to Hash for Structured Data 35 Item 11: Create Namespaces by Nesting Code in Modules 38 Item 12: Understand the Different Flavors of Equality 43 Item 13: Implement Comparison via "<=>" and the Comparable Module 49 Item 14: Share Private State through Protected Methods 53 Item 15: Prefer Class Instance Variables to Class Variables 55 Chapter 3: Collections 59 Item 16: Duplicate Collections Passed as Arguments before Mutating Them 59 Item 17: Use the Array Method to Convert nil and Scalar Objects into Arrays 63 Item 18: Consider Set for Efficient Element Inclusion Checking 66 Item 19: Know How to Fold Collections with reduce 70 Item 20: Consider Using a Default Hash Value 74 Item 21: Prefer Delegation to Inheriting from Collection Classes 79 Chapter 4: Exceptions 85 Item 22: Prefer Custom Exceptions to Raising Strings 85 Item 23: Rescue the Most Specific Exception Possible 90 Item 24: Manage Resources with Blocks and ensure 94 Item 25: Exit ensure Clauses by Flowing Off the End 97 Item 26: Bound retry Attempts, Vary Their Frequency, and Keep an Audit Trail 100 Item 27: Prefer throw to raise for Jumping Out of Scope 104 Chapter 5: Metaprogramming 107 Item 28: Familiarize Yourself with Module and Class Hooks 107 Item 29: Invoke super from within Class Hooks 114 Item 30: Prefer define_method to method_missing 115 Item 31: Know the Difference between

Peter J. Jones is a freelance software developer and a senior instructor for programming workshops taught by Devalot.com. He has been programming in Ruby since 2005, and has written and taught several development workshops, including an 11-week Ruby class for beginners.