Hello Ruby

Transcript

1. Hello Ruby :) Felipe Pelizaro Gentil @fpgentil Carlos Eduardo Ribeiro @duduribeiro
2. ruby /ˈruːbi/
3. Ruby ..is a dynamic, open source programming language with a focus on simplicity and productivity. It has an elegant syntax that is natural to read and easy to write. https://www.ruby-lang.org/en/documentation/
4. Reserved words
5. Ruby Version Manager (RVM) RVM is a command-line tool which allows you to easily install, manage, and work with multiple ruby $ gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 $ curl -sSL https://get.rvm.io | bash -s stable https://github.com/rvm/rvm
6. IRB … stands for “interactive Ruby” and is a tool to interactively execute Ruby expressions read from the standard input. $ irb
7. Methods
8. if / unless
9. Loops
10. or || && and http://devblog.avdi.org/2010/08/02/using-and-and-or-in-ruby/ and is useful for chaining related operations together until one of them returns nil or false or is useful for chaining expressions together. The best way to think about the chains constructed with or is as series of fallbacks: try this, if that fails try this, and so on. For instance:
11. ||= Double Pipe / Or Equals http://www.rubyinside.com/what-rubys-double-pipe-or-equals-really-does-5488.html
12. Array
13. Hash
14. Symbols Symbol objects represent names and some strings inside the Ruby interpreter
15. map http://railspikes.com/2008/8/11/understanding-map-and-reduce Returns a new array with the results of running block once for every element in enum. http://apidock.com/ruby/Enumerable/map
16. reduce / inject http://railspikes.com/2008/8/11/understanding-map-and-reduce Combines all elements of enum by applying a binary operation, specified by a block or a symbol that names a method or operator.
17. reduce / inject http://apidock.com/ruby/v1_9_3_392/Enumerable/inject
18. attr_accessor attr_writer attr_reader defines getter and setter defines only getter defines only setter
19. Classes
20. Opening Classes
21. Clojures function that can be stored as a variable
22. Ruby and its 4 types of clojures Blocks Procedures (aka Procs) lambdas Method Objects
23. Blocks
24. Procedures (Procs) a block that can be saved for reusable code
25. lambdas • a Proc that check the number of arguments • Diminutive return, in other words, a Proc return will stop 
 a method, lambdas will return their value and let the method 
 continue
26. Method Objects
27. Exercises • Generate a Fibonacci sequence in an array until 500 • Create a method that receives N parameter and return their sum • Create a method that receives a string and check if its a palindrome
28. Fibonacci
29. Sum
30. Palindrome
31. Gems • What? essentially a Ruby plugin • Why? code reuse as open-source, it provides others the opportunity
 to contribute by adding features • How? $ gem install bundler $ bundle gem my_gem
32. RubyGems
34. Tests!!!!!!!!
35. Rspec / Minitest http://tenderlovemaking.com/2015/01/23/my-experience-with-minitest-and-rspec.html
36. Rspec / Minitest https://github.com/rspec/rspec https://github.com/seattlerb/minitest
37. Exercise Create a GEM that performs the 4 basic math operations - SUM - SUBTRACTION - MULTIPLICATION - DIVISION Tip: folder already created ~/Desktop/Hello Ruby/hello_ruby_calculator