certainty

((UP   "CREATE TABLE IF NOT EXISTS edge (in_vertex INTEGER,out_vertex INTEGER)")
 (DOWN "DROP TABLE IF EXISTS edge"))

certainty

((UP ,(lambda (db) (do-something-nifty-with db)))
 (DOWN ,(lambda (db) (undo-something-nifty-with db))))

certainty

((UP "CREATE TABLE vertices (id INTEGER, name STRING)")
 (DOWN (#f . "You must not remove vertices") ))

certainty

(use nomads nomads-sql-de-lite fmt fmt-color filepath)

(migration-directory "./migrations")
(database-credentials "test.db")

(define (get-version)
  (let ((version (get-environment-variable "VERSION")))
    (if version
        (or (string->number version) (string->symbol version))
        'latest)))

certainty

class Base < ActiveRecord::Base
  self.abstract_class = true
end

# the table foobars has the column abort:string

class Foobar < Base
  self.table_name = "foobars"
end

certainty

class MissmatchRecorder
  attr_reader :record
  def initialize
    @record = ""
  end
  
  def <<(msg)
    @record << msg
  end
  

certainty

your_map = @users.inject({}) do |m,u|
 duplicates = @users.select{ |u2| u.id != u2.id && u.email == u2.email }
 (m[u.email] ||= []).concat(duplicates) unless duplicates.empty?
 m
end

certainty

class Company < ActiveRecord::Base
  attr_accessible :name 

  has_many :parent_associations, :class_name => 'Association', :foreign_key => 'child_id'
  has_many :child_associations, :class_name => 'Association', :foreign_key => 'parent_id'

  has_many :parents, :through => :parent_associations, :source => :parent
  has_many :children, :through => :child_associations, :source => :child
end

certainty

Object.send(:alias_method,:_m,:method)

class Foo
  def reverse(thing)
    thing.reverse
  end

  def map_reverse(things)
     things.map(&_m(:reverse))
  end

certainty

class User < ActiveRecord::Base
    validates :phone_number, presence: true, length: { is: 11 }, if: :gsm_number_empty?,   unless: :password_or_email_changed?
    validates :gsm_number,   presence: true, length: { is: 11 }, if: :phone_number_empty?, unless: :password_or_email_changed?
private
    def password_or_email_changed?
       encrypted_password_changed? || email_changed? 
    end
    
    def phone_number_empty?
      !phone_number.present?