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Amir Barylko - RoR Training MavenThought Inc. - June 2010

AMIR BARYLKOIRON RUBY AND .NET

A MATCH MADE INHEAVEN.NET USER GROUP

SEP 2010


WHO AM I?

• Architect

• Developer

• Mentor

• Great cook

• The one who’s entertaining you for the next hour!


CONTACT AND MATERIALS

• Contact me: [email protected], @abarylko

• Download: http://www.orthocoders.com/presentations.

Amir Barylko - Iron Ruby and .NET MavenThought Inc. - Sep 2010

RUBY INTRODynamic languages

TestingIRB

Constructs


DYNAMIC LANGUAGES

High level

Dynamically typed

Runtime over compile time

Closures

Reflection

Platform independent


.NET CLR

Iron Ruby DLR CLR


DEVELOPERS TOOLBOX

•Make your toolbox grow!

• The right tool for the job

• Not a replacement

• Combine strengths

• Problem solving


WELCOME TO RUBY

Created in mid-90s by “Matz” Matsumoto in Japan

Smalltalk, Perl influences

Dynamic typing

Object Oriented

Automatic memory management

Several implementations: MRI, YARB, JRuby

Totally free!!


RUBY FEATURES

Everything is an expression

Metaprogramming

Closures

Garbage collection

Exceptions

Operator overloading, flexible syntax

Powerful standard library


RUBY SUPPORT

Hundreds of books

User conferences all over the world

Active community (you can create a conf in your own city and top Ruby coders will go there to teach others, invite them and see)

Lots of great web sites: basecamp, twitter, 43 things, hulu, scribd, slideshare, Justin.tv

Lots of web frameworks inspired by Ruby on Rails


SET UP

Download IronRuby installer

Put the bin folder on the path

That’s it!


INTERACTIVE IRON RUBY SHELL

c:\> ir.exe

> puts “hello”

hello

=> nil

> "Hello World! " * 2

=> "Hello World! Hello World!

"

> ((1 + 5) * 3) ** 2

=> 324

> x = 1.upto(5).to_a

=> [1, 2, 3, 4, 5]

> x.join

=> "12345"


BASIC TYPES

Numbers

1.class => Fixnum

1.1.class => Float

(120**100).class => Bignum

3.times {puts “he “}


BASIC TYPES II

• Strings

'he ' + 'he' => he he

“That's right” => That's right

'He said “hi”' => He said “hi”

“He said \“hi\”” => He said “hi”

“1 + 1 is #{1+1}” => 1 + 1 is 2

"#{'Ho! '*3}Merry Christmas" =>Ho! Ho! Ho! Merry

Christmas


BASIC TYPES III

Arrays

a = [1, 5.5, “nice!”]

1 == a.first

1 == a[0]

nil == a[10]

a[1] = 3.14

a.each {|elem| puts elem}

a.sort


BASIC TYPES IV

• Hashesh = {“one” => 1, 1 => “one”}

h[“one”] == 1

h[1] == “one”

h[“two”] == nil

h.keys == [“one”, 1] (or is it [1, “one”] ?)

h.values == [“one”, 1] (or is it [1, “one”] ?)

h[“one”] = 1.0


BASIC TYPES V

Symbols: constant names. No need to declare, guaranteed uniqueness, fast comparison

:apple == :apple

:orange != :banana

[:all, :those, :symbols]

{:ca => “Canada”, :ar => “Argentina”, :es => “Spain”}


CONTROL STRUCTURES

if

while

if count < 20 puts “need more”elsif count < 40 puts “perfect”else puts “too many”end

while count < 100 && need_more buy(1)end


CONTROL STRUCTURES II

Statement modifiers

buy while need_more?

buy(5) if need_more?

buy until left == 0

buy unless left < 5


CONTROL STRUCTURES III

• Case

case left

when 0..5

dont_buy_more

when 6..10

buy(1)

when 10..100

buy(5)

end


METHODS

Simple

Default arguments

def play(movie_path)....end

def play(movie_path, auto_start = true, wrap = false)....end


METHODS II

Return value: the last expression evaluated, no need for explicit return

No need for parenthesis on call without arguments (same syntax to call a method and a field)

def votes(voted, num_votes) voted && num_votes || nilend

buy() == buy

movie.play() == movie.play


METHODS III

No need also with arguments (but careful!! only if you know what you are doing)

movie.play “Pulp fiction”, false, true


RUBY INTRO IIClassesMixin

Enumerable


CLASSES & OBJECTS

Initializer and instance variablesclass Movie def initialize(name) @name = name end

def play puts %Q{Playing “#{@name}”. Enjoy!} endend

m = Movie.new(“Pulp fiction”)m.play

=> Playing “Pulp fiction”. Enjoy!


CLASSES & OBJECTS II Attributesclass Movie def initialize(name) @name = name end

def name @name end

def name=(value) @name = value end

end

m = Movie.new('Brazil').name = “Pulp fiction”

# attr_reader :name

# attr_writter :name

# attr_accessor :name}


CODE ORGANIZATION

Code in files with .rb extension

Require 'movie' will read movie.rb file and make its methods available to the current file

Require 'media/movie' will read file from media dir relative to the current working dir$LOAD_PATH << 'media'require 'movie'


CODE ORGANIZATION II

Relative to this file:require File.join(File.dirname(__FILE__), 'media/movie')


MIXINS

What about module “instance methods”?

One of the greatest Ruby features!

You can define functions in Modules, and get them added to your classes.

Great code reuse,

Multiple inheritance alternative.

Code organization


ENUMERABLE

Enumerable mixin, from the standard library documentation:

The Enumerable mixin provides collection

classes with several traversal and

searching methods, and with the ability to

sort. The class must provide a method each,

which yields successive members of the

collection


ENUMERABLE II

It provides useful methods such as:

map

to_a

take_while

count

inject


EXAMPLESrSpec

Enumerable Mixinmissing_method

SinatraBDD Cucumber

DSL


RSPEC TESTING LIBRARY

require File.dirname(__FILE__) + "/../main/MavenThought.MovieLibrary/bin/Debug/MavenThought.MovieLibrary.dll"require 'rubygems'require 'spec'include MavenThought::MovieLibrary

describe Library do it "should be created empty" do lib = Library.new lib.contents.should be_empty end it "should add an element" do lib = Library.new m = Movie.new 'Blazing Saddles' lib.add m lib.contents.should include(m) lib.contents.count.should == 1 end end


EXTEND LIBRARYWITH METHOD MISSING

require File.dirname(__FILE__) + "/../main/MavenThought.MovieLibrary/bin/Debug/MavenThought.MovieLibrary.dll"

require 'rubygems'

include MavenThought::MovieLibrary

# Extend library to use method missing to add find_byclass Library

def method_missing(m, *args) if m.id2name.include?( "find_by" ) field = m.id2name.sub /find_by_/, "" contents.find_all( lambda{ |m| m.send(field) == args[0] } ) else super end end end

l = Library.new

l.add Movie.new('Blazing Saddles', System::DateTime.new(1972, 1, 1))l.add Movie.new('Spaceballs', System::DateTime.new(1984, 1, 1))


SIMPLE WEB WITH SINATRA

require 'rubygems'require 'sinatra'require 'haml'require 'singleton'

require File.dirname(__FILE__) + "/../main/MavenThought.MovieLibrary/bin/Debug/MavenThought.MovieLibrary.dll"include MavenThought::MovieLibrary

class Library include Singletonend

# indexget '/' do @movies = Library.instance.contents haml :indexend

# createpost '/' do m = Movie.new(params[:title]) Library.instance.add m redirect '/'end


BDD WITH CUCUMBER

Feature: Addition In order to make my library grow As a registered user I want to add movies to the library

Scenario: Add a movie Given I have an empty library When I add the following movies: | title | release_date | | Blazing Saddles | Feb 7, 1974 | | Young Frankenstein | Dec 15, 1974 | | Spaceballs | Jun 24, 1987 |

Then The library should have 3 movies And "Blazing Saddles" should be in the list with release date "Feb 7, 1974" And "Young Frankenstein" should be in the list with release date "Dec 15, 1974" And "Spaceballs" should be in the list with release date "Jun 24, 1987"


CUCUMBER STEPS

require File.dirname(__FILE__) + "/../../main/MavenThought.MovieLibrary/bin/Debug/MavenThought.MovieLibrary.dll"

include MavenThought::MovieLibrary

Given /^I have an empty library$/ do @lib = Library.newend

When /^I add the following movies:$/ do |table| table.hashes.each do |row| movie = Movie.new row[:title], System::DateTime.parse(row[:release_date]) @lib.add movie endend

Then /^The library should have (.*) movies$/ do |count| @lib.contents.count.should == count.to_iend

Then /^"([^\"]*)" should be in the list with release date "([^\"]*)"$/ do |title, release| @lib.contents.find( lambda { |m| m.title == title and m.release_date == System::DateTime.parse(release) } ).should_not be_nilend


DSL IRAKE

task :default => [:build]desc "Builds the project"task :build do call_target msbuild_cmd, :buildend

desc "Rebuild the application by cleaning and then building"task :rebuild => [:clean, :build] do #nothing to do....end

desc "Runs all the tests"task :test => ["test:all"]


DSL IICRON - WHENEVER

every 10.minutes do runner "MyModel.some_process" rake "my:rake:task" command "/usr/bin/my_great_command" end

every 2.days, :at => '4:30am' do command "/usr/bin/my_great_command" end

QUESTIONS?

(Don’t be shy)


CONTACT AND MATERIALS

• Contact me: [email protected], @abarylko

• Download: http://www.orthocoders.com/presentations.


ONLINE RESOURCES

IronRuby: http://ironruby.net/

The Ruby Bible (a.k.a. Pickaxe) http://ruby-doc.org/docs/ProgrammingRuby/

Ruby language site: http://www.ruby-lang.org

Technology

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