Brief Ruby/Ruby on Rails intro

1. RUBY A PROGRAMMER’S BEST FRIEND
2. Background
3. Yukihiro “Matz” Matsumoto
4. I hope to see Ruby help every programmer in the world to be productive, and to enjoy programming, and to be happy. at is the primary purpose of Ruby language.” “
5. - Programmer happiness - Principle of least astonishment - Human readable - Beautiful syntax Principles
6. - RubyGems, Bundler & Rake - Multiple implementations (MRI, JRuby, Rubinius, mruby, MacRuby, Topaz, …) - Solid Standard Library Ecosystem
7. - MINASWAN - Self re ective - Open - Quirky Community
8. The Language A Sales Pitch
10. Object–oriented 1
11. 5.times { print "We love Ruby" }
12. class Animal def eat(food) puts "Animal eating" end end my_animal = Animal.new animal.eat # => "Animal eating"
13. class Dog < Animal def eat(food) puts "Dog eating" super end end
14. module Stomach def digest(food) # ... end end
15. class Dog < Animal include Stomach end my_dog = Dog.new dog.digest
16. -199.abs # => 199 "Foobar".split("").uniq.sort.join # => "abFor" nil.class # => "NilClass"
17. Dynamically typed Duck–typing 2
18. if dog.is_a? Animal dog.eat end dog.eat if dog.respond_to?(:eat)
19. Monkey–patching (Duck–punching) 3
20. … if it walks like a duck and talks like a duck, it’s a duck, right? So if this duck is not giving you the noise that you want, you’ve got to just punch that duck until it returns what you expect.” “
21. class String def yell "#{self.upcase}!" end end "hello".yell # => "HELLO!"
22. Meta–programming 4
23. class Greeter def method_missing(name, *args) name = name.to_s if name =~ /^hello_/ puts "Hello, #{name.gsub(/^hello_/, '')}!" else super end end end Greeter.new.hello_john # => "Hello, john!"
24. Blocks & Lambdas 5
25. [1, 2, 3].map { |i| i ** 2 } # => [1, 4, 9]
26. def greet(&block) # ... greeting = yield("John") # ... end greet do |name| "Hello, #{name}!" end
27. A word on speed
28. Ruby on Rails An (even shorter) sales pitch
30. - Open Source Web Framework - MVC - Convention over Con guration - DRY - Opinionated Principles
31. - Generators - ORM - Restful routing - Included webserver Features
32. $ gem install rails $ rails new blog $ cd blog $ rails generate scaffold post title content:text $ rake db:migrate $ rails server
33. author = Author.find_by :name => "John" author.posts.first.title
34. Book.where(:title => 'Tale of Two Cities') .first_or_create
35. class Account < ActiveRecord::Base # Returns all accounts with unread messages. def self.with_unread_messages joins(:messages).merge(Message.unread) end end