Learning Ruby

Appendix B. Answers to Review Questions

Chapter 1 Review Questions

1. What is the nickname of the inventor of Ruby? Matz

2. Ruby came out in 1995. What other programming language was released to the public that year? Java

3. Is everyone who writes a programming book morally or otherwise obligated to write a “Hello, World!” program? No!

4. What does the abbreviation irb stand for? Interactive Ruby, the line-oriented Ruby sandbox

5. What is Ruby’s killer app? Ruby on Rails

6. What is the name of the funny book on Ruby? why’s (poignant) guide to Ruby

7. Who wrote the pickaxe book? Dave Thomas

8. What’s one of the author’s favorite programming environments on the Mac? TextMate

Chapter 2 Review Questions

1. What is one of the main differences between a class and a module? You can instantiate a class, but not a module

2. What module does the Object class include? Kernel

3. What syntax do you use to form block comments? =begin/=end

4. What special character begins an instance variable? A class variable? A global variable? @, @@, $

5. What is the main feature that distinguishes a constant? A constant must begin with an uppercase letter

6. When a method ends with a ?, what does that signify by convention? Returns true or false

7. A block is a sort of nameless _____________. Method or function

8. What is a proc? A stored procedure, with context

9. What is the most important characteristic of a symbol? It occupies a single memory location

10. What is RDoc? The Ruby documentation tool

Chapter 3 Review Questions

1. Why is case/when somewhat more convenient than if/elsif ...