Account.transaction(david, mary) do
    david.withdrawal(100)
    mary.deposit(100)
end

class Account < ActiveRecord::Base
    validates_presence_of     :subdomain, :name, :email_address, :password
    validates_uniqueness_of   :subdomain
    validates_acceptance_of   :terms_of_service, :on => :create
    validates_confirmation_of :password, :email_addressm, :on => :create
end

class Project < ActiveRecord::Base
    belongs_to              :portfolio
    has_one                 :project_manager, :class_name => "Person"
    has_many                :milestones, :dependent => true
    has_and_belongs_to_many :categories, :join_table => "categorizations"
end

class Account < ActiveRecord::Base
    has_many :people do
        def find_or_create_by_name(name)
            first_name, *last_name = name.split
            last_name = last_name.join " "

            find_or_create_by_first_name_and_last_name(first_name, last_name)
        end
    end
end

person = Account.find(:first).people.find_or_create_by_name("Richard Feynman")
person.first_name # => "Richard"
person.last_name  # => "Feynman"

class Post < ActiveRecord::Base
    belongs_to :weblog
    has_many   :comments
    has_one    :author, :class => "Person"
end

class Comment < ActiveRecord::Base
    def sel.search(query)
        find(:all, :conditions => [ "body = ?", query ])
    end
end

# SELECT * FROM comments WHERE post_id=1 AND body='hi';
Post.find(1).comments.search "hi"

class Story < ActiveRecord::Base
    belongs_to   :iteration
    acts_as_list :scope => :iteration
end

story.move_higher
story.move_to_bottom

FIXME:

class Author < ActiveRecord::Base
    has_many :authorships
    has_many :books, :through => :authorships
end

class Book < ActiveRecord::Base
    has_many :authorships
    has_many :authors, :through => :authorships
end

class Authorship < ActiveRecord::Base
    belongs_to :author
    belongs_to :book
end

david, awrd = Author.find(1), Book.find(1)
david.authorships.create(
    :book => awrd, :contribution => "partial", :written_in => "Denmark"
)

david.authorships.first.written_in # => "Denamrk"
david.books.first # => awrd

FIXME:

class Person < ActiveRecord::Base
    has_many :taggings, :as => :taggable, :dependent => true
    has_many :tags, :through => :taggings
end

class Message < ActiveRecord::Base
    has_many :taggings, :as => :taggable, :dependent => true
    has_many :tags, :through => :taggings
end

class Tagging < ActiveRecord::Base
    belongs_to :tag
    belongs_to :taggable, :polymorfic => true
end

class Tag < ActiveRecord::Base
    has_many :taggings

    def on(*taggables)
        taggables.each {|taggable| taggings.create :taggable => taggable }
    end

    def tagged
        taggings.collect {|tagging| tagging.taggable }
    end
end

david   = Person.find(1)
welcome = Message.find(1)
summer  = Tag.find_or_create_by_name "Summer"

summer.on(david, welcome)

david.tags   # => [ summer ]
welcome.tags # => [ summer ]

summer.tagged # => [ david, welcome ]

class Person < ActiveRecord::Base
    acts_as_tagable
end

class Message < ActiveRecord::Base
    acts_as_tagable
end

FIXME:

class StoryController < ApplicationController
    session       :off,             :only => :feed
    verify        :method => :post, :only => [ :coment ]
    before_filter :authenticate,    :only => [ :new, :edit ]

    def show
        @story = Story.find(params[:id])
    end

    def new
        if request.story?
            @story = Story.create(params[:story])
            cookies[:last_story] = {
                :value   => @story.create_at,
                :expires => 20.years.from_now
            }

            flash[:notice] = "Created new story"
            redirect_to :action => "show", :id => @story
        else
            @story = Story.new
            render :layout => "creation"
        end
    end
end

<h1>Create a new iteration</h1>
<p>
    You already have <%= pluralize(@iterations.size, "iteration") %>.

    The last one started like this:
    "<%= truncate(@iterations.first.description, 10) %>"
</p>

<% form_for :iteration, Iteration.new do |i| %>
    Title:<br/>
    <%= i.text_field :title %>

    Description:<br/>
    <%= i.text_area :title, :size => "20x40" %>

    Completion target:<br/>
    <%= i.date_select :completed_on, :discard_year => true %>

    <% fields_for :story, Story.new do |s| %>
        Headline:<br/>
        <%= s.text_field :headline, :length => 30, :class => "big" %>

        Difficulty:<br/>
        <% s.select :difficulty, %w(easy medium hard) %>
    <% end %>
<% end %>

...or <%= link_to "Cancel", :action => "overvire" %>

xml.instruct!
xml.rss("version" => "2.0", "xmlns:dc" => "http://purl.org/dc/elements/1.1/") do
    xml.channel do
        xml.title "Backpack"
        xml.link(url_for(:action => "start", :only_path => false))
        xml.description "Tracking changes for your Backpack pages"
        xml.language "en-us"
        xml.ttl "40"

        for event in @events
            xml.item do
                xml.title(event.headline)
                xml.description(event.description)
                xml.pubDate(event.created_at.to_s(:rfc822))
                xml.guid(event.id)
                xml.link(page_url(:id => event.page))
            end
        end
    end
end

Rails::Initializer.run do |config|
    config.frameworks -= [ :action_web_service ]
    config.load_paths += [ "#{RAILS_ROOT}/app/services" ]
    config.log_level   = :debug

    config.action_controller.session_store        = :active_record_store
    config.action_controller.fragment_cache_store = :file_store

    config.active_record.default_timezone = :utc
    config.active_record.schema_format    = :ruby
end

ActionController::Routing::Routes.draw do |map|
    map.start   '', :controller => 'pages', :action => 'start'
    map.signup  'signup', :controller => 'account', :action => 'new'
    map.page    'page/:id', :controller => 'pages', :action => 'show'
    map.connect 'page/:id/:action', :controller => 'pages'
    map.connect 'images/icons/:icon_file', :controller => "assets", :action => "missing_icon"

    map.feed    'feed/:token', :controller => "account", :action => "feed"
    map.ical    'ical/:token', ::controller => "reminders", :action => "ical"
end

set :application, "backpack"
set :repository,  "svn+ssh://somewhere/nice"

set :gateway, "gateway.37signals.com"

role :app, "app1.37signals.com", :primary => true
role :app, "app2.37signals.com"
role :app, "app3.37signals.com"
role :web, "web1.37signals.com", :primary => true
role :web, "web2.37signals.com"
role :web, "db.37signals.com",   :primary => true