Intro to Ruby (and RSpec)
Download as KEY, PDF•0 likes•637 views
Ruby was created by Yukihiro "Matz" Matsumoto with a focus on programmer productivity and usability. It is a dynamically typed, interpreted programming language that was first released in 1996. Ruby supports object-oriented programming and features like blocks, lambdas, and regular expressions. Popular implementations of the Ruby virtual machine include MRI, YARV, JRuby, Rubinius, IronRuby, and MacRuby. RSpec is a testing framework for Ruby that uses describe and it blocks to specify expectations for code examples to verify.
Intro to Ruby (and RSpec)
- 2. THE RUBY LANGUAGE • Originally by Yukihiro "Matz" Matsumoto • “Ruby is designed for programmer productivity and fun, following the principles of good user interface design. He stresses that systems design needs to emphasize human, rather than computer, needs.” http://en.wikipedia.org/wiki/Ruby_(programming_language)#History • Ruby 1.0 was released in 1996.
- 3. RUBY LANGUAGE OVERVIEW • Dynamically typed • Interpreted • Can be modified at runtime • Object oriented • Blocks & lambdas • Nice support for Regular Expressions
- 4. RUBY VERSIONS ruby -v •1.8.6 – Still around but mostly supplanted by 1.8.7 •1.8.7 – some 1.9 features, compatible w/ 1.8.6 •1.9.2 – latest version, many VMs, Rails 2.3+
- 5. RUBY VMS • MRI (Matz's Ruby Interpreter) the original Ruby, default for 1.8 • YARV (yet another Ruby VM) faster than MRI, default for 1.9 • JRuby (Java) • Rubinius (pure ruby) • IronRuby (.NET) • MacRuby, HotCocoa • HotRuby/RubyJS (Flash/Javascript)
- 6. LETS GET STARTED • IRB: InteractiveRuBy >> 4 >> 4 + 4
- 7. EVERYTHING IS AN OBJECT “test”.upcase “test”.class “test”.methods
- 8. EVERYTHING EVALUATES TO SOMETHING 2+2 (2+2).zero?
- 9. METHODS ARE MESSAGES thing.do(4) thing.do 4 thing.send “do”, 4
- 10. OPERATORS ARE METHODS thing.do 4 3+2 thing.do(4) 3.+(2) thing.send “do”, 4 3.send "+", 2
- 11. DEFINING CLASSES • Let’s write some code!
- 12. INTRODUCTION TO RSPEC • Describe the feature • Verify expectation
- 13. RSPEC SYNTAX describe Something do end
- 14. RSPEC SYNTAX describe Something do it "should do whatever it should do" end
- 15. RSPEC SYNTAX describe Something do it "should do whatever it should do" do end end
- 16. RSPEC SYNTAX describe Something do it "should do whatever it should do" do s = Something.new end end
- 17. RSPEC SYNTAX describe Something do it "should do whatever it should do" do s = Something.new s.do_whatever(3, 2, 1) end end
- 18. RSPEC SYNTAX describe Something do it "should do whatever it should do" do s = Something.new s.do_whatever(3, 2, 1).should == "blast off!" end end
- 19. RSPEC SYNTAX describe Something do it "should do whatever it should do" do s = Something.new s.do_whatever(3, 2, 1).should == "blast off!" end end
- 20. • Let's try it!