Ruby for .NET developers

Introduction to Ruby for .NET developers.

Transcript

1. By Max Titov maxtitov.me
 Ninja Software Operations Ruby for .NET
 Developers
2. Objective: learn and compare ▶  What is Ruby? ▶  Ruby basics ▶  Ruby specialties ▶  Ruby ecosystem ▶  So why Ruby? ▶  How to get started?
4. What is Ruby?
5. Creator "I wanted a scripting language that was more powerful than Perl, and more object- oriented than Python. That's why I decided to design my own language.”      Yukihiro  (Matz)  Matsumoto
6. Facts ▶  First  “Hello  World”  in  1995  (.NET  2002,  C#   2001)   ▶  Ruby  is  opensource   ▶  Inspired  by:  Perl,  Smalltalk,  Lisp,  Python  …   ▶  Philosophy:  Designed  for  programmer     producTvity  and  fun.  
7. Ruby Basics
8. First taste of Ruby code class Apple! NAME = "Apple"! attr_accessor :size, :color! ! def initialize size! @size = size! end! ! def taste! puts "Sweet #{@color} #{NAME} of size #{size}"! end! end! ! apple = Apple.new 'big'! apple.color = 'red' ! apple.taste # Sweet red Apple of size big!
9. I know, feels like
10. Similarities ▶  Large standard library (Not so big as .NET Framework but feels enough) ▶  The are classes, methods, variables, properties. ▶  Access control modifiers ▶  Closures (Lambdas) ▶  Exceptions ▶  Garbage collector
11. Ruby is Dynamic ▶  No need to declare variables var = "Ruby is Dynamic"! var.class #String! var = 1! var.class #Fixnum!
12. Ruby is Strong Typed ▶  Like in .NET there is no type juggling.
 You need to convert between types. a = "1"! b = 2! a + b #TypeError: can`t convert Fixnum into String! a.to_i + b # 3! ! !
13. Everything is an Object ▶  All classes are drived from base class named Class! ▶  Unlike .NET there is no structs
14. Everything is an Object ▶  So even primitive Types are an objects 
 10.times {puts "I am sexy and I know it!"}! # I am sexy and I know it!! # I am sexy and I know it!! # I am sexy and I know it!! # I am sexy and I know it!! # I am sexy and I know it!! # ....(10 times)....!
15. Everything is an Object ▶  Operators are simply object methods. class Fixnum < Integer! def + numeric! # sum code! end! end!
16. Ruby is Flexible ▶  Core Ruby code could be easy altered. class Numeric ! def toSquare! self * self! end! end! ! 2.toSquare # 4!
17. Ruby is Concise ▶  Properties could be defined in old school way class Person! #getter! def name! @name! end! ! #setter! def name= name! @name = name! end! end
18. Ruby is Concise ▶  Or in more convenient style class Person! #getter and setter, for several properties! attr_accessor :name , :nickname! ! #getter! attr_reader :gender! ! #setter! attr_writer :age! end
19. Some questions to you ▶  Constants, start from capital or not? ▶  Field names, prefixed with underscore or not? ▶  How many coding guide lines is there actually? ▶  Microsoft Framework Design Guidelines ▶  IDesign C# coding standards ▶  Your company coding standard ▶  Your own coding standard. (Professional choice)
20. Ruby is Strict ▶  Autocracy took over the Ruby community.
21. Ruby is Strict Ruby syntaxes mostly dictates naming conventions: ▶  localVariable ▶  @instanceVariable ▶  @@classVariable ▶  $globalVariable ▶  Constant ▶  ClassName ▶  method_name
22. Ruby is Strict ▶  95% of ruby developers use same code style. ▶  Other 5% are a new comers, that will adept code conventions soon.
23. Forever alone in the world of naming conventions. So in Ruby world you don’t feel like:
24. And Ruby Is Forgiving ▶  Parenthesis are optional ▶  No need in semicolon at the end of each line
25. Ruby specialties
26. Duck typing What really makes object an object? How can I recognize that object is a Duck?
27. Duck typing Behavior
28. Duck typing ▶  Definition: When I see a bird that walks like a duck and swims like a duck and quacks like a duck, I call that bird a duck. (Wikipedia)
29. So, is it a duck? Swim?  Yes   Can  Quack?  Yes     Is  it  a  duck?   Definitely!  
30. And this? Swim?  Yes   Can  Quack?  Yes.  Kind  of   strange,  but  sTll  it     make  quack  like  sound     Is  it  a  duck?   Looks  like!  
31. How, about this? Swim?  Badly,  but  yes.     Can  Quack?  Yeah,  make     Plenty  of  sounds  but,  can     quack  also.     Is  it  a  duck?   Sort  of  weird  duck,  but  sTll   yes!  
32. Or, probably this? Swim?  Yep   Can  quack?  Can     make  weird  quack   sounds.     Is  it  duck?   Trying  very  hard  
33. Duck Typing ▶  So, everything that could respond to several criteria's that makes us believe
 that object is a duck, can be recognized as a duck. ▶  But what that means from programmer perspective and how to implement it?
34. What if I told you there is no abstract classes and interfaces?
35. But there is Modules and Mixins! ▶  Modules define pieces of reusable code that couldn’t be instantiated. ▶  Modules provides a namespace functionality and prevent name clashes
36. Namespaces in Ruby module System! module Windows! module Forms! module MessageBox! ! ! !def MessageBox.Show message! !puts message! ! ! !end! end! end! end! end! ! include System::Windows::Forms! MessageBox.Show 'Namespacing in ruby’
37. Modules and Mixins ▶  Modules could be “mixed in” to any class that satisfy conventions described in documentation (Should quack and swim like a duck). ▶  In .net Mixins using ReMix http://remix.codeplex.com/
38. Lets see how it works by implementing Enumerable
39. In .NET we usually do this ▶  We need to implement two interfaces ▶  IEnumerable! ▶  IEnumerator
40. In .NET we usually do this class People : IEnumerable! {! !IEnumerator GetEnumerator()! !{! ! !return (IEnumerator) new PeopleEnumerator();! !}! }! ! public class PeopleEnumerator : IEnumerator! {! !public Person Current;! !public void Reset();! !public bool MoveNext();! }! ! public class Person! {! }
41. How it’s done in Ruby ▶  From Enumerable module documentation:
 The Enumerable mixin provides collection classes with several traversal and searching methods, and with the ability to sort. The client class must provide a method “each”, which yields successive members of the collection.
42. How it’s done in Ruby class MyCollection! include Enumerable! def each! #yields result! end! end!
43. That was easy!
44. But static typing and interfaces make me safe! Really?
45. In Ruby world developers used to write unit tests for this
46. Document and organize their code better # The <code>Enumerable</code> mixin provides collection classes with! # several traversal and searching methods, and with the ability to! # sort. The class must provide a method <code>each</code>, which! # yields successive members of the collection. If! # <code>Enumerable#max</code>, <code>#min</code>, or! # <code>#sort</code> is used, the objects in the collection must also! # implement a meaningful <code><=></code> operator, as these methods! # rely on an ordering between members of the collection.! module Enumerable! # enum.to_a -> array! # enum.entries -> array! !# Returns an array containing the items in <i>enum</i>.! # ! # (1..7).to_a #=> [1, 2, 3, 4, 5, 6, 7]! # { 'a'=>1, 'b'=>2, 'c'=>3 }.to_a #=> [["a", 1], ["b", 2], !# ! ! ! ! ! ! ! ! ! ! !["c", 3]]! def to_a()! #This is a stub, used for indexing! end !
47. Closures in Ruby ▶  Closures in Ruby called Blocks 
 names = ["Max", "Alex", "Dima"].map do |name|! name.downcase! end! puts names! # max! # alex! # dima! !
48. Ruby metaprogramming ▶  Metaprogramming is the writing of computer programs that write or manipulate other programs (or themselves) as their data, or that do part of the work at compile time that would otherwise be done at runtime. (Wikipedia) ▶  Keep programs DRY – Don’t repeat yourself.
49. Where is example? In all cinemas of your town 
 Next time “Ruby metaprogramming”
50. Ruby Ecosystem
51. Frameworks Ruby ▶  Ruby on Rails, Merb ▶  Sinatra ▶  Radiant, Mephisto .NET ▶  ASP.NET MVC, FunuMVC ▶  Nancy ▶  Umbraco, DotNetNuke
52. Tools Ruby ▶  Any TextEditor (RubyMine IDE) ▶  Rake ▶  Gems ▶  Gems and Bundler ▶  TestUnit, minitest ▶  Cucumber, RSpec, Shoulda .NET ▶  Visual Studio, MonoDevelop ▶  MSBuild, NAnt ▶  Dll’s ▶  NuGet ▶  MSUnit, NUnit … ▶  NSpec, SpecFlow
53. So Why Ruby?
54. So Why Ruby? ▶  All hot stuff is here J ▶  Benefits of interpreted language ▶  Quick prototyping with Rails ▶  It’s fun and it’s going to make your better! ▶  And definitely it will sabotage what you believe in.
55. Feel more Rubier now? I hope so J
56. Ruby tutorial 101 Interactive Ruby tutorial: ▶  http://tryruby.org/ Online course: ▶  http://www.coursera.org/course/saas/

57. Books ▶  Programming Ruby (Pick Axe book)
 By Thomas D., Fowler C., Hunt A. ▶  Design Patterns In Ruby
 By Russ Olsen ▶  Search Google for: Learn Ruby
58. Follow the ruby side we have cookies J
59. Yep, we really do! J
60. Questions? Ruby for .NET developers By Max Titov Get presentation: www.maxtitov.me Get in touch: eolexe@gmail.com Twitter: eolexe