Ruby for C# Developers

Ruby for C# Developers Cory Foy http://www.cornetdesign.com St. Louis Code Camp May 6 th , 2006

Overview ,[object Object],[object Object],[object Object],[object Object],[object Object]

What is Ruby? ,[object Object],[object Object],[object Object],[object Object],[object Object]

What is Ruby? ,[object Object],class Person attr_accessor :name, :age # attributes we can set and retrieve def initialize(name, age) # constructor method @name = name # store name and age for later retrieval @age = age.to_i # (store age as integer) end def inspect # This method retrieves saved values "#@name (#@age)" # in a readable format end end p1 = Person.new('elmo', 4) # elmo is the name, 4 is the age puts p1.inspect # prints “elmo (4)”

Will It Change Your Life? ,[object Object],[object Object],[object Object],[object Object]

Ruby Basics ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Ruby Basics - Variables ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Ruby Basics - Classes ,[object Object],class Move attr_accessor :up, :right def initialize(up, right) @up = up @right = right end end

Ruby Basics - Methods ,[object Object],class Move def up @up end def right return @right end end

Ruby Basics - Methods ,[object Object],class Move def initialize(up, right) @up = up @right = right end end

Ruby Basics - Methods ,[object Object],class Move def self.create return Move.new end def Move.logger return @@logger end end

Ruby Basics - Properties ,[object Object],class Move def up @up end end class Move def up=(val) @up = val end end move = Move.new move.up = 15 puts move.up #15

Ruby Basics - Properties ,[object Object],class Move attr_accessor :up #Same thing as last slide end move = Move.new move.up = 15 puts move.up #15

Ruby Basics - Properties ,[object Object],class Move attr_reader :up #Can’t write attr_writer :down #Can’t read end move = Move.new move.up = 15 #error d = move.down #error

Ruby Basics - Exceptions ,[object Object],[object Object],[object Object]

Ruby Basics - Exceptions process_file = File.open(“testfile.csv”) begin #put exceptional code in begin/end block #...process file rescue IOError => io_error puts “IOException occurred. Retrying.” retry #starts block over from begin rescue => other_error puts “Bad stuff happened: “ + other_error else #happens if no exceptions occur puts “No errors in processing. Yippee!” ensure # similar to finally in .NET/Java process_file.close unless process_file.nil? end

Ruby Basics – Access Control ,[object Object],[object Object]

Ruby Basics – Access Control ,[object Object],class Move private def calculate_move end #Any subsequent methods will be private until.. public def show_move end #Any subsequent methods will now be public end

Ruby Basics – Access Control ,[object Object],class Move def calculate_move end def show_move end public :show_move protected :calculate_move end

Ruby Basics - Imports ,[object Object],require ‘calculator’ class Move def calculate_move return @up * Calculator::MIN_MOVE end end

Ruby Basics - Imports ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Ruby Basics – Duck Typing ,[object Object],[object Object],[object Object],[object Object],[object Object]

Ruby Basics – Duck Typing ,[object Object],[object Object],class CarWash def accept_customer(car) end end ,[object Object]

Ruby Basics – Duck Typing ,[object Object]

Ruby Basics – Duck Typing ,[object Object],[object Object]

Ruby Basics – Duck Typing ,[object Object],Class CarWash def accept_customer(car) if car.respond_to?(:drive_to) @car = car wash_car else reject_customer end end end

Ruby Basics – Unit Tests ,[object Object],[object Object],[object Object],[object Object],[object Object]

Ruby Basics – Unit Tests ,[object Object],[object Object],[object Object]

Ruby Basics – Unit Tests ,[object Object],[object Object],[object Object],[object Object]

Ruby Basics – Unit Tests ,[object Object],class TestToaster < Test::Unit::TestCase def test_toast_bread toaster = Toaster.new bread = WonderBread.new toaster.heat_level = 5 toaster.toast(bread) assert_equal(“Nicely toasted”, bread.status) end end

Ruby Basics – Unit Tests ,[object Object],root@dilbert $ruby testtoaster.rb Loaded suite testtoaster Started E Finished in 0.0 seconds. 1) Error: test_toast_bread(TestToaster): NameError: uninitialized constant TestToaster::Toaster testtoaster.rb:4:in `test_toast_bread' 1 tests, 0 assertions, 0 failures, 1 errors

Ruby Basics – Unit Tests ,[object Object],class Toaster attr_accessor :heat_level def toast(bread) end end class WonderBread attr_accessor :status end

Ruby Basics – Unit Tests ,[object Object],root@dilbert $ruby testtoaster.rb Loaded suite testtoaster Started F Finished in 0.093 seconds. 1) Failure: test_toast_bread(TestToaster) [testtoaster.rb:10]: <"Nicely toasted"> expected but was <nil>. 1 tests, 1 assertions, 1 failures, 0 errors

Ruby Basics – Unit Tests ,[object Object],class Toaster def toast(bread) bread.status = “Nicely toasted” end end root@dilbert $ruby testtoaster.rb Loaded suite testtoaster Started . Finished in 0.0 seconds. 1 tests, 1 assertions, 0 failures, 0 errors

Ruby Basics – Unit Tests ,[object Object],[object Object]

Advanced Ruby - Modules ,[object Object],[object Object],[object Object],[object Object],[object Object]

Advanced Ruby - Blocks ,[object Object],{ puts “Ho” } 3.times do puts “Ho “ end #prints “Ho Ho Ho”

Advanced Ruby - Blocks ,[object Object],def format_print puts “Confidential. Do Not Disseminate.” yield puts “© SomeCorp, 2006” end format_print { puts “My name is Earl!” } -> Confidential. Do Not Disseminate. -> My name is Earl! -> © SomeCorp, 2006

Advanced Ruby - Blocks ,[object Object],def MyConnection.open(*args) conn = Connection.open(*args) if block_given? yield conn #passes conn to the block conn.close #closes conn when block finishes end return conn end

Advanced Ruby - Iterators ,[object Object],[object Object]

Advanced Ruby - Iterators ,[object Object],def fib_up_to(max) i1, i2 = 1, 1 while i1 <= max yield i1 i1, i2 = i2, i1+i2 # parallel assignment end end fib_up_to(100) {|f| print f + “ “} -> 1 1 2 3 5 8 13 21 34 55 89

Advanced Ruby - Modules ,[object Object],module Kite def Kite.fly end end module Plane def Plane.fly end end

Advanced Ruby - Mixins ,[object Object],[object Object],[object Object]

Advanced Ruby - Mixins module Print def print puts “Company Confidential” yield end end class Document include Print #... end doc = Document.new doc.print { “Fourth Quarter looks great!” } -> Company Confidential -> Fourth Quarter looks great!

Advanced Ruby - Reflection ,[object Object],String myString = "test"; int len = (int)myString .GetType() .InvokeMember("Length", System.Reflection.BindingFlags.GetProperty, null, myString, null); Console.WriteLine("Length: " + len.ToString());

Advanced Ruby - Reflection ,[object Object],myString = “Test” puts myString.send(:length) # 4

Advanced Ruby - Reflection ,[object Object],#print out all of the objects in our system ObjectSpace.each_object(Class) {|c| puts c} #Get all the methods on an object “ Some String”.methods #see if an object responds to a certain method obj.respond_to?(:length) #see if an object is a type obj.kind_of?(Numeric) obj.instance_of?(FixNum)

Ruby Basics – Other Goodies ,[object Object],[object Object],[object Object]

Ruby and .NET ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Ruby and .NET ,[object Object],[object Object],[object Object],[object Object],[object Object]

Ruby Resources ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Ruby for C# Developers

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (9)

Similar to Ruby for C# Developers

Similar to Ruby for C# Developers (20)

More from Cory Foy

More from Cory Foy (20)

Recently uploaded

Recently uploaded (20)

Ruby for C# Developers