ryanlecompte

# The following fails with a failure to call "x=" private method
String.send(:attr_accessor, :x)
s = ""
s.x = 100

# The following works:
class String
  self.send(:attr_accessor, :x)
end
s = ""

ryanlecompte

>> module M
>>   x = 100
>>   define_method(:x=) {|v| x = v }
>>   define_method(:x) { x }
>> end
=> #<Proc:0x0000010102dfd0@(irb):4 (lambda)>
>> class A
>>   include M
>> end
=> A

ryanlecompte

require 'open-uri'

url = 'http://www.hobotraveler.com/uploaded_images/207-249-tiger-nut-efio-togo-food-798405.jpg'
f = File.open('image.jpg', 'w')
open(url) { |io| f.puts(io.read) }
f.close

ryanlecompte

def m1
  commands = {:exit => Proc.new { break }}
  loop do
    commands[:exit].call
  end
  puts "Done!"
end

m1

ryanlecompte

ruby-1.9.2-head :001 > module M1
ruby-1.9.2-head :002?>   def self.m1
ruby-1.9.2-head :003?>     "self.m1 in M1"
ruby-1.9.2-head :004?>     end
ruby-1.9.2-head :005?>   end
 => nil 
ruby-1.9.2-head :006 > module M2
ruby-1.9.2-head :007?>   include M1
ruby-1.9.2-head :008?>   def self.m2
ruby-1.9.2-head :009?>     m1

ryanlecompte

module M
  def self.included(base)
    base.class_eval do
      singleton_class = (class << self; self; end)
      singleton_class.send(:define_method, :foo) do
          puts "in foo! base is #{base}"
      end
    end
  end
end

ryanlecompte

class C
  def initialize(*args)
    puts "hi from C"
  end
end

module M
 def self.included(clazz)
   clazz.class_eval do
     alias_method :old_initialize, :initialize

ryanlecompte

ruby-1.9.2-head :001 > class C
ruby-1.9.2-head :002?>   def ==(o)
ruby-1.9.2-head :003?>     puts "==(0)"
ruby-1.9.2-head :004?>     super
ruby-1.9.2-head :005?>     end
ruby-1.9.2-head :006?>   def eql?(o)
ruby-1.9.2-head :007?>     puts "eql?(o)"
ruby-1.9.2-head :008?>     super
ruby-1.9.2-head :009?>     end
ruby-1.9.2-head :010?>   def hash

ryanlecompte

module M
  def m1
    puts "hi from M"
  end
  
  def handle(&block)
    block.call
  end

  def handle2(&block)

ryanlecompte

dict = {}
'aardvark'.chars.inject(dict) { |dict,c| dict[c] = {} }

def find(key, dict)
  current_dict = dict
  key.chars.each do |c|
    return nil unless current_dict.has_key?(c)
    current_dict = current_dict[c]
  end
end