Updated koan directory from src.

* 'master' of git://github.com/JEG2/ruby_koans:
  Adding Regular Expression koans.
  Fixing a bug that was causing some number Koans to be presolved.

README.rdoc

@@ -1,29 +1,29 @@
 = EdgeCase Ruby Koans
 
-The Ruby Koans walk you along the path to enlightenment in order to learn Ruby. 
-The goal is to learn the Ruby language, syntax, structure, and some common 
+The Ruby Koans walk you along the path to enlightenment in order to learn Ruby.
+The goal is to learn the Ruby language, syntax, structure, and some common
 functions and libraries. We also teach you culture. Testing is not just something we
-pay lip service to, but something we live.  It is essential in your quest to learn 
-and do great things in the language.  
+pay lip service to, but something we live.  It is essential in your quest to learn
+and do great things in the language.
 
 == The Structure
 
-The koans are broken out into areas by file, hashes are covered in about_hashes.rb, 
-modules are introduced in about_modules.rb, etc.  They are presented in order in the 
-path_to_enlightenment.rb file.  
+The koans are broken out into areas by file, hashes are covered in about_hashes.rb,
+modules are introduced in about_modules.rb, etc.  They are presented in order in the
+path_to_enlightenment.rb file.
 
-Each koan builds up your knowledge of Ruby and builds upon itself.  It will stop at 
-the first place you need to correct.  
+Each koan builds up your knowledge of Ruby and builds upon itself.  It will stop at
+the first place you need to correct.
 
-Some koans simply need to have the correct answer substituted for an incorrect one. 
-Some, however, require you to supply your own answer.  If you see the method +__+ (a 
-double underscore) listed, it is a hint to you to supply your own code in order to 
-make it work correctly.  
+Some koans simply need to have the correct answer substituted for an incorrect one.
+Some, however, require you to supply your own answer.  If you see the method +__+ (a
+double underscore) listed, it is a hint to you to supply your own code in order to
+make it work correctly.
 
 == Installing Ruby
 
-If you do not have Ruby setup, please visit http://ruby-lang.org/en/downloads/ for 
-operating specific instructions.  In order to run this you need ruby and rake 
+If you do not have Ruby setup, please visit http://ruby-lang.org/en/downloads/ for
+operating specific instructions.  In order to run this you need ruby and rake
 installed. To check the installations simply type:
 
 *nix platforms from any terminal window:
@@ -33,11 +33,11 @@ installed. To check the installations simply type:
 
 Windows from the command prompt (cmd.exe)
 
-   c:\ruby --version 
+   c:\ruby --version
    c:\rake --version
-   
-Any response for Ruby with a version number greater than 1.8 is fine (should be 
-around 1.8.6 or more). Any version of rake will do.  
+
+Any response for Ruby with a version number greater than 1.8 is fine (should be
+around 1.8.6 or more). Any version of rake will do.
 
 == The Path To Enlightenment
 
@@ -48,18 +48,18 @@ recommended way to run them as we might build more functionality into this task)
 
     [ruby_koans] $ rake                           # runs the default target :walk_the_path
     [ruby_koans] $ ruby path_to_enlightenment.rb  # simply call the file directly
-    
+
 Windows is the same thing
 
     c:\ruby_koans\rake                             # runs the default target :walk_the_path
     c:\ruby_koans\ruby path_to_enlightenment.rb    # simply call the file directly
-    
+
 === Red, Green, Refactor
 
 In test-driven development the mantra has always been, red, green, refactor.  Write a
 failing test and run it (red), make the test pass (green), then refactor it (that is
 look at the code and see if you can make it any better.  In this case you will need
-to run the koan and see it fail (red), make the test pass (green), then take a 
+to run the koan and see it fail (red), make the test pass (green), then take a
 moment and reflect upon the test to see what it is teaching you and improve the
 code to better communicate its intent (refactor).
 
@@ -68,26 +68,26 @@ The very first time you run it you will see the following output:
     [ ruby_koans ] $ rake
     (in /Users/person/dev/ruby_koans)
     cd koans
-    
+
     Thinking AboutAsserts
       test_assert_truth has damaged your karma.
-    
+
     You have not yet reached enlightenment ...
     <false> is not true.
-    
+
     Please meditate on the following code:
     ./about_asserts.rb:10:in `test_assert_truth'
     path_to_enlightenment.rb:27
 
     mountains are merely mountains
-    
+
 You have come to your first stage. If you notice it is telling you where to look for
 the first solution:
 
     Please meditate on the following code:
     ./about_asserts.rb:10:in `test_assert_truth'
     path_to_enlightenment.rb:27
-    
+
 We then open up the about_asserts.rb file and look at the first test:
 
     # We shall contemplate truth by testing reality, via asserts.
@@ -97,13 +97,13 @@ We then open up the about_asserts.rb file and look at the first test:
 
 We then change the +false+ to +true+ and run the test again.  After you are
 done, think about what you are learning.  In this case, ignore everything except
-the method name (+test_assert_truth+) and the parts inside the method (everything 
-before the +end+).  
- 
-In this case the goal is for you to see that if you pass a value to the +assert+ 
+the method name (+test_assert_truth+) and the parts inside the method (everything
+before the +end+).
+
+In this case the goal is for you to see that if you pass a value to the +assert+
 method, it will either ensure it is +true+ and continue on, or fail if in fact
-the statement is +false+.   
- 
+the statement is +false+.
+
 == Inspiration
 
 A special thanks to Mike Clark and Ara Howard for inspiring this

Rakefile

@@ -21,6 +21,7 @@ module Koans
     line = line.gsub(/\b____\([^\)]+\)/, "____")
     line = line.gsub(/\b___\([^\)]+\)/, "___")
     line = line.gsub(/\b__\([^\)]+\)/, "__")
+    line = line.gsub(/\b_n_\([^\)]+\)/, "_n_")
     line = line.gsub(%r(/\#\{__\}/), "/__/")
     line
   end
@@ -28,6 +29,8 @@ module Koans
   def Koans.make_koan_file(infile, outfile)
     if infile =~ /edgecase/
       cp infile, outfile
+    elsif infile =~ /autotest/
+      cp_r infile, outfile
     else
       open(infile) do |ins|
         open(outfile, "w") do |outs|

koans/README.rdoc

@@ -1,29 +1,29 @@
 = EdgeCase Ruby Koans
 
-The Ruby Koans walk you along the path to enlightenment in order to learn Ruby. 
-The goal is to learn the Ruby language, syntax, structure, and some common 
+The Ruby Koans walk you along the path to enlightenment in order to learn Ruby.
+The goal is to learn the Ruby language, syntax, structure, and some common
 functions and libraries. We also teach you culture. Testing is not just something we
-pay lip service to, but something we live.  It is essential in your quest to learn 
-and do great things in the language.  
+pay lip service to, but something we live.  It is essential in your quest to learn
+and do great things in the language.
 
 == The Structure
 
-The koans are broken out into areas by file, hashes are covered in about_hashes.rb, 
-modules are introduced in about_modules.rb, etc.  They are presented in order in the 
-path_to_enlightenment.rb file.  
+The koans are broken out into areas by file, hashes are covered in about_hashes.rb,
+modules are introduced in about_modules.rb, etc.  They are presented in order in the
+path_to_enlightenment.rb file.
 
-Each koan builds up your knowledge of Ruby and builds upon itself.  It will stop at 
-the first place you need to correct.  
+Each koan builds up your knowledge of Ruby and builds upon itself.  It will stop at
+the first place you need to correct.
 
-Some koans simply need to have the correct answer substituted for an incorrect one. 
-Some, however, require you to supply your own answer.  If you see the method +__+ (a 
-double underscore) listed, it is a hint to you to supply your own code in order to 
-make it work correctly.  
+Some koans simply need to have the correct answer substituted for an incorrect one.
+Some, however, require you to supply your own answer.  If you see the method +__+ (a
+double underscore) listed, it is a hint to you to supply your own code in order to
+make it work correctly.
 
 == Installing Ruby
 
-If you do not have Ruby setup, please visit http://ruby-lang.org/en/downloads/ for 
-operating specific instructions.  In order to run this you need ruby and rake 
+If you do not have Ruby setup, please visit http://ruby-lang.org/en/downloads/ for
+operating specific instructions.  In order to run this you need ruby and rake
 installed. To check the installations simply type:
 
 *nix platforms from any terminal window:
@@ -33,11 +33,11 @@ installed. To check the installations simply type:
 
 Windows from the command prompt (cmd.exe)
 
-   c:\ruby --version 
+   c:\ruby --version
    c:\rake --version
-   
-Any response for Ruby with a version number greater than 1.8 is fine (should be 
-around 1.8.6 or more). Any version of rake will do.  
+
+Any response for Ruby with a version number greater than 1.8 is fine (should be
+around 1.8.6 or more). Any version of rake will do.
 
 == The Path To Enlightenment
 
@@ -48,18 +48,18 @@ recommended way to run them as we might build more functionality into this task)
 
     [ruby_koans] $ rake                           # runs the default target :walk_the_path
     [ruby_koans] $ ruby path_to_enlightenment.rb  # simply call the file directly
-    
+
 Windows is the same thing
 
     c:\ruby_koans\rake                             # runs the default target :walk_the_path
     c:\ruby_koans\ruby path_to_enlightenment.rb    # simply call the file directly
-    
+
 === Red, Green, Refactor
 
 In test-driven development the mantra has always been, red, green, refactor.  Write a
 failing test and run it (red), make the test pass (green), then refactor it (that is
 look at the code and see if you can make it any better.  In this case you will need
-to run the koan and see it fail (red), make the test pass (green), then take a 
+to run the koan and see it fail (red), make the test pass (green), then take a
 moment and reflect upon the test to see what it is teaching you and improve the
 code to better communicate its intent (refactor).
 
@@ -68,26 +68,26 @@ The very first time you run it you will see the following output:
     [ ruby_koans ] $ rake
     (in /Users/person/dev/ruby_koans)
     cd koans
-    
+
     Thinking AboutAsserts
       test_assert_truth has damaged your karma.
-    
+
     You have not yet reached enlightenment ...
     <false> is not true.
-    
+
     Please meditate on the following code:
     ./about_asserts.rb:10:in `test_assert_truth'
     path_to_enlightenment.rb:27
 
     mountains are merely mountains
-    
+
 You have come to your first stage. If you notice it is telling you where to look for
 the first solution:
 
     Please meditate on the following code:
     ./about_asserts.rb:10:in `test_assert_truth'
     path_to_enlightenment.rb:27
-    
+
 We then open up the about_asserts.rb file and look at the first test:
 
     # We shall contemplate truth by testing reality, via asserts.
@@ -97,13 +97,13 @@ We then open up the about_asserts.rb file and look at the first test:
 
 We then change the +false+ to +true+ and run the test again.  After you are
 done, think about what you are learning.  In this case, ignore everything except
-the method name (+test_assert_truth+) and the parts inside the method (everything 
-before the +end+).  
- 
-In this case the goal is for you to see that if you pass a value to the +assert+ 
+the method name (+test_assert_truth+) and the parts inside the method (everything
+before the +end+).
+
+In this case the goal is for you to see that if you pass a value to the +assert+
 method, it will either ensure it is +true+ and continue on, or fail if in fact
-the statement is +false+.   
- 
+the statement is +false+.
+
 == Inspiration
 
 A special thanks to Mike Clark and Ara Howard for inspiring this

koans/about_array_assignment.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutArrayAssignment < EdgeCase::Koan
   def test_non_parallel_assignment
@@ -35,4 +35,11 @@ class AboutArrayAssignment < EdgeCase::Koan
     assert_equal __, first_name
   end
 
+  def test_swapping_with_parallel_assignment
+    first_name = "Roy"
+    last_name = "Rob"
+    first_name, last_name = last_name, first_name
+    assert_equal __, first_name
+    assert_equal __, last_name
+  end
 end

koans/about_arrays.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutArrays < EdgeCase::Koan
   def test_creating_arrays

koans/about_asserts.rb

@@ -1,7 +1,7 @@
 #!/usr/bin/env ruby
 # -*- ruby -*-
 
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutAsserts < EdgeCase::Koan
 

koans/about_blocks.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutBlocks < EdgeCase::Koan
   def method_with_block

koans/about_class_methods.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutClassMethods < EdgeCase::Koan
   class Dog
@@ -19,11 +19,11 @@ class AboutClassMethods < EdgeCase::Koan
 
   def test_objects_have_methods
     fido = Dog.new
-    assert_equal __, fido.methods.size
+    assert fido.methods.size > _n_
   end
 
   def test_classes_have_methods
-    assert_equal __, Dog.methods.size
+    assert Dog.methods.size > _n_
   end
 
   def test_you_can_define_methods_on_individual_objects

koans/about_classes.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutClasses < EdgeCase::Koan
   class Dog
@@ -43,7 +43,7 @@ class AboutClasses < EdgeCase::Koan
     fido = Dog2.new
     fido.set_name("Fido")
 
-    assert_equal __, fido.instance_variable_get("@name")    
+    assert_equal __, fido.instance_variable_get("@name")
   end
 
   def test_you_can_rip_the_value_out_using_instance_eval
@@ -89,7 +89,7 @@ class AboutClasses < EdgeCase::Koan
 
     assert_equal __, fido.name
   end
-  
+
   # ------------------------------------------------------------------
 
   class Dog5
@@ -125,7 +125,7 @@ class AboutClasses < EdgeCase::Koan
     # THINK ABOUT IT:
     # Why is this so?
   end
-  
+
   def test_different_objects_have_difference_instance_variables
     fido = Dog6.new("Fido")
     rover = Dog6.new("Rover")
@@ -186,5 +186,5 @@ class AboutClasses < EdgeCase::Koan
     assert_equal __, "STRING".to_s
     assert_equal __, "STRING".inspect
   end
- 
+
 end

koans/about_constants.rb

@@ -0,0 +1,87 @@
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
+
+C = "top level"
+
+class AboutConstants < EdgeCase::Koan
+
+  C = "nested"
+
+  def test_nested_constants_may_also_be_referenced_with_relative_paths
+    assert_equal __, C
+  end
+
+  def test_top_level_constants_are_referenced_by_double_colons
+    assert_equal __, ::C
+  end
+
+  def test_nested_constants_are_referenced_by_their_complete_path
+    assert_equal __, AboutConstants::C
+    assert_equal __, ::AboutConstants::C
+  end
+
+  # ------------------------------------------------------------------
+
+  class Animal
+    LEGS = 4
+    def legs_in_animal
+      LEGS
+    end
+
+    class NestedAnimal
+      def legs_in_nested_animal
+        LEGS
+      end
+    end
+  end
+
+  def test_nested_classes_inherit_constants_from_enclosing_classes
+    assert_equal __, Animal::NestedAnimal.new.legs_in_nested_animal
+  end
+
+  # ------------------------------------------------------------------
+
+  class Reptile < Animal
+    def legs_in_reptile
+      LEGS
+    end
+  end
+
+  def test_subclasses_inherit_constants_from_parent_classes
+    assert_equal __, Reptile.new.legs_in_reptile
+  end
+
+  # ------------------------------------------------------------------
+
+  class MyAnimals
+    LEGS = 2
+
+    class Bird < Animal
+      def legs_in_bird
+        LEGS
+      end
+    end
+  end
+
+  def test_who_wins_with_both_nested_and_inherited_constants
+    assert_equal __, MyAnimals::Bird.new.legs_in_bird
+  end
+
+  # QUESTION: Which has precedence: The constant in the lexical scope,
+  # or the constant from the inheritance heirarachy?
+
+  # ------------------------------------------------------------------
+
+  class MyAnimals::Oyster < Animal
+    def legs_in_oyster
+      LEGS
+    end
+  end
+
+  def test_who_wins_with_explicit_scoping_on_class_definition
+    assert_equal __, MyAnimals::Oyster.new.legs_in_oyster
+  end
+
+  # QUESTION: Now Which has precedence: The constant in the lexical
+  # scope, or the constant from the inheritance heirarachy?  Why is it
+  # different than the previous answer?
+end

koans/about_control_statements.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutControlStatements < EdgeCase::Koan
 
@@ -11,7 +11,7 @@ class AboutControlStatements < EdgeCase::Koan
     assert_equal __, result
   end
 
-  def test_if_then_else_statements
+  def test_if_then_statements
     result = :default_value
     if true
       result = :true_value

koans/about_dice_project.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class DiceSet
   attr_reader :values

koans/about_exceptions.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutExceptions < EdgeCase::Koan
 

koans/about_hashes.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutHashes < EdgeCase::Koan
   def test_creating_hashes
@@ -48,7 +48,7 @@ class AboutHashes < EdgeCase::Koan
 
   def test_hash_values
     hash = { :one => "uno", :two => "dos" }
-    assert_equal __, hash.keys.size
+    assert_equal __, hash.values.size
     assert_equal __, hash.values.include?("uno")
     assert_equal __, hash.values.include?("dos")
     assert_equal Array, hash.values.class

koans/about_inheritance.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutInheritance < EdgeCase::Koan
   class Dog

koans/about_iteration.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutIteration < EdgeCase::Koan
 

koans/about_message_passing.rb

@@ -1,28 +1,28 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutMessagePassing < EdgeCase::Koan
-  
+
   class MessageCatcher
     def caught?
       true
     end
   end
-    
+
   def test_methods_can_be_called_directly
     mc = MessageCatcher.new
-    
-    assert mc.caught?    
+
+    assert mc.caught?
   end
-  
+
   def test_methods_can_be_invoked_by_sending_the_message
     mc = MessageCatcher.new
-    
+
     assert mc.send(:caught?)
   end
-  
+
   def test_methods_can_be_invoked_more_dynamically
     mc = MessageCatcher.new
-    
+
     assert mc.send("caught?")
     assert mc.send("caught" + __ )    # What do you need to add to the first string?
     assert mc.send("CAUGHT?".____ )      # What would you need to do to the string?
@@ -40,23 +40,22 @@ class AboutMessagePassing < EdgeCase::Koan
 
   def test_classes_can_be_asked_if_they_know_how_to_respond
     mc = MessageCatcher.new
-    
+
     assert_equal __, mc.respond_to?(:caught?)
     assert_equal __, mc.respond_to?(:does_not_exist)
   end
-  
+
   # ------------------------------------------------------------------
 
   class MessageCatcher
     def add_a_payload(*args)
-      return :empty unless args
       args
     end
   end
-  
+
   def test_sending_a_message_with_arguments
     mc = MessageCatcher.new
-    
+
     assert_equal __, mc.add_a_payload
     assert_equal __, mc.send(:add_a_payload)
 
@@ -90,6 +89,18 @@ class AboutMessagePassing < EdgeCase::Koan
     #
     # If the method :method_missing causes the NoMethodError, then
     # what would happen if we redefine method_missing?
+    #
+    # NOTE:
+    #
+    # In Ruby 1.8 the method_missing method is public and can be
+    # called as shown above.  However, in Ruby 1.9 the method_missing
+    # method is private.  We explicitly made it public in the testing
+    # framework so this example works in both versions of Ruby.  Just
+    # keep in mind you can't call method_missing like that in Ruby
+    # 1.9. normally.
+    #
+    # Thanks.  We now return you to your regularly schedule Ruby
+    # Koans.
   end
 
   # ------------------------------------------------------------------

koans/about_methods.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 def my_global_method(a,b)
   a + b
@@ -10,14 +10,14 @@ class AboutMethods < EdgeCase::Koan
     assert_equal __, my_global_method(2,3)
   end
 
-  def test_calling_global_methods_without_parenthesis
+  def test_calling_global_methods_without_parentheses
     result = my_global_method 2, 3
     assert_equal __, result
   end
 
   # (NOTE: We are Using eval below because the example code is
   # considered to be syntactically invalid).
-  def test_sometimes_missing_parenthesis_are_ambiguous
+  def test_sometimes_missing_parentheses_are_ambiguous
     eval "assert_equal 5, my_global_method 2, 3" # ENABLE CHECK
     #
     # Ruby doesn't know if you mean:

koans/about_modules.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutModules < EdgeCase::Koan
   module Nameable

koans/about_nil.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutNil < EdgeCase::Koan
   def test_nil_is_an_object

koans/about_open_classes.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutOpenClasses < EdgeCase::Koan
   class Dog

koans/about_proxy_object_project.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 # Project: Create a Proxy Class
 #

koans/about_regular_expressions.rb

@@ -0,0 +1,159 @@
+# -*- coding: utf-8 -*-
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
+
+class AboutRegularExpressions < EdgeCase::Koan
+  def test_a_pattern_is_a_regular_expression
+    assert_equal Regexp, /pattern/.class
+  end
+
+  def test_a_regexp_can_search_a_string_for_matching_content
+    assert_equal "match", "some matching content"[/match/]
+  end
+
+  def test_a_failed_match_returns_nil
+    assert_equal __, "some matching content"[/missing/]
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_question_mark_means_optional
+    assert_equal __, "abbcccddddeeeee"[/ab?/]
+    assert_equal __, "abbcccddddeeeee"[/az?/]
+  end
+
+  def test_plus_means_one_or_more
+    assert_equal __, "abbcccddddeeeee"[/bc+/]
+  end
+
+  def test_asterisk_means_zero_or_more
+    assert_equal __, "abbcccddddeeeee"[/ab*/]
+    assert_equal __, "abbcccddddeeeee"[/az*/]
+    assert_equal __, "abbcccddddeeeee"[/z*/]
+
+    # THINK ABOUT IT:
+    #
+    # When would * fail to match?
+  end
+
+  # THINK ABOUT IT:
+  #
+  # We say that the repetition operators above are "greedy."
+  #
+  # Why?
+
+  # ------------------------------------------------------------------
+
+  def test_the_left_most_match_wins
+    assert_equal __, "abbccc az"[/az*/]
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_character_classes_give_options_for_a_character
+    animals = ["cat", "bat", "rat", "zat"]
+    assert_equal __, animals.select { |a| a[/[cbr]at/] }
+  end
+
+  def test_slash_d_is_a_shortcut_for_a_digit_character_class
+    assert_equal __, "the number is 42"[/[0123456789]+/]
+    assert_equal __, "the number is 42"[/\d+/]
+  end
+
+  def test_character_classes_can_include_ranges
+    assert_equal __, "the number is 42"[/[0-9]+/]
+  end
+
+  def test_slash_s_is_a_shortcut_for_a_whitespace_character_class
+    assert_equal __, "space: \t\n"[/\s+/]
+  end
+
+  def test_slash_w_is_a_shortcut_for_a_word_character_class
+    # NOTE:  This is more like how a programmer might define a word.
+    assert_equal __, "variable_1 = 42"[/[a-zA-Z0-9_]+/]
+    assert_equal __, "variable_1 = 42"[/\w+/]
+  end
+
+  def test_period_is_a_shortcut_for_any_non_newline_character
+    assert_equal __, "abc\n123"[/a.+/]
+  end
+
+  def test_a_character_class_can_be_negated
+    assert_equal __, "the number is 42"[/[^0-9]+/]
+  end
+
+  def test_shortcut_character_classes_are_negated_with_capitals
+    assert_equal __, "the number is 42"[/\D+/]
+    assert_equal __, "space: \t\n"[/\S+/]
+    assert_equal __, "variable_1 = 42"[/\W+/]
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_slash_a_anchors_to_the_start_of_the_string
+    assert_equal __, "start end"[/\Astart/]
+    assert_equal __, "start end"[/\Aend/]
+  end
+
+  def test_slash_z_anchors_to_the_end_of_the_string
+    assert_equal __, "start end"[/end\z/]
+    assert_equal __, "start end"[/start\z/]
+  end
+
+  def test_caret_anchors_to_the_start_of_lines
+    assert_equal __, "num 42\n2 lines"[/^\d+/]
+  end
+
+  def test_dollar_sign_anchors_to_the_end_of_lines
+    assert_equal __, "2 lines\nnum 42"[/\d+$/]
+  end
+
+  def test_slash_b_anchors_to_a_word_boundary
+    assert_equal __, "bovine vines"[/\bvine./]
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_parentheses_group_contents
+    assert_equal __, "ahahaha"[/(ha)+/]
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_parentheses_also_capture_matched_content_by_number
+    assert_equal __, "Gray, James"[/(\w+), (\w+)/, 1]
+    assert_equal __, "Gray, James"[/(\w+), (\w+)/, 2]
+  end
+
+  def test_variables_can_also_be_used_to_access_captures
+    assert_equal __, "Name:  Gray, James"[/(\w+), (\w+)/]
+    assert_equal __, $1
+    assert_equal __, $2
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_a_vertical_pipe_means_or
+    grays = /(James|Dana|Summer) Gray/
+    assert_equal __, "James Gray"[grays]
+    assert_equal __, "Summer Gray"[grays, 1]
+    assert_equal __, "Jim Gray"[grays, 1]
+  end
+
+  # THINK ABOUT IT:
+  #
+  # Explain the difference between a character class ([…]) and alternation (|).
+
+  # ------------------------------------------------------------------
+
+  def test_scan_is_like_find_all
+    assert_equal __, "one two-three".scan(/\w+/)
+  end
+
+  def test_sub_is_like_find_and_replace
+    assert_equal __, "one two-three".sub(/(t\w*)/) { $1[0, 1] }
+  end
+
+  def test_gsub_is_like_find_and_replace_all
+    assert_equal __, "one two-three".gsub(/(t\w*)/) { $1[0, 1] }
+  end
+end

koans/about_sandwich_code.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutUsingBlocks < EdgeCase::Koan
 

koans/about_scope.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutScope < EdgeCase::Koan
   module Jims
@@ -28,7 +28,7 @@ class AboutScope < EdgeCase::Koan
     rover = Joes::Dog.new
     assert_equal __, fido.identify
     assert_equal __, rover.identify
-    
+
     assert_not_equal fido.class, rover.class
     assert_not_equal Jims::Dog, Joes::Dog
   end
@@ -41,7 +41,7 @@ class AboutScope < EdgeCase::Koan
   def test_bare_bones_class_names_assume_the_current_scope
     assert_equal __, AboutScope::String == String
   end
-  
+
   def test_nested_string_is_not_the_same_as_the_system_string
     assert_equal __, String == "HI".class
   end
@@ -74,6 +74,6 @@ class AboutScope < EdgeCase::Koan
 
   def test_you_can_get_a_list_of_constants_for_any_class_or_module
     assert_equal __, Jims.constants
-    assert_equal __, Object.constants.size
+    assert Object.constants.size > _n_
   end
 end

koans/about_scoring_project.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 # Greed is a dice game where you roll up to five dice to accumulate
 # points.  The following "score" function will be used calculate the

koans/about_strings.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutStrings < EdgeCase::Koan
   def test_double_quoted_strings_are_strings
@@ -146,11 +146,20 @@ EOS
     # Surprised?
   end
 
-  def test_single_characters_are_represented_by_integers
-    assert_equal __, ?a
-    assert_equal __, ?a == 97
+  in_ruby_version("1.8") do
+    def test_in_ruby_1_8_single_characters_are_represented_by_integers
+      assert_equal __, ?a
+      assert_equal __, ?a == 97
 
-    assert_equal __, ?b == (?a + 1)
+      assert_equal __, ?b == (?a + 1)
+    end
+  end
+
+  in_ruby_version("1.9") do
+    def test_in_ruby_1_9_single_characters_are_represented_by_strings
+      assert_equal __, ?a
+      assert_equal __, ?a == 97
+    end
   end
 
   def test_strings_can_be_split
@@ -165,8 +174,8 @@ EOS
     assert_equal [__, __, __, __], words
 
     # NOTE: Patterns are formed from Regular Expressions.  Ruby has a
-    # very powerful Regular Expression library.  Unfortunately, time
-    # does not permit us to explore it in detail in Ruby 101.
+    # very powerful Regular Expression library.  We will become
+    # enlightened about them soon.
   end
 
   def test_strings_can_be_joined

koans/about_triangle_project.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 # You need to write the triangle method in the file 'triangle.rb'
 require 'triangle.rb'

koans/about_triangle_project_2.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 # You need to write the triangle method in the file 'triangle.rb'
 require 'triangle.rb'
@@ -9,6 +9,7 @@ class AboutTriangleAssignment2 < EdgeCase::Koan
   def test_illegal_triangles_throw_exceptions
     assert_raise(TriangleError) do triangle(0, 0, 0) end
     assert_raise(TriangleError) do triangle(3, 4, -5) end
+    assert_raise(TriangleError) do triangle(1, 1, 3) end
     assert_raise(TriangleError) do triangle(2, 4, 2) end 
  end
 end

koans/about_true_and_false.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutTrueAndFalse < EdgeCase::Koan
   def truth_value(condition)

koans/autotest/discover.rb

@@ -0,0 +1,3 @@
+Autotest.add_discovery do
+  "rubykoan" if File.exist? 'path_to_enlightenment.rb'
+end

koans/autotest/rubykoan.rb

@@ -0,0 +1,24 @@
+require 'autotest'
+
+class Autotest::Rubykoan < Autotest
+  def initialize
+    super
+    @exceptions = /\.txt|Rakefile|\.rdoc/
+
+    self.order = :alpha
+    self.add_mapping(/^about_.*rb$/) do |filename, _|
+      filename
+    end 
+
+  end
+
+  def make_test_cmd files_to_test
+    "#{ruby}  'path_to_enlightenment.rb'"
+  end 
+
+  # quiet test/unit chatter
+  def handle_results(results)
+  end
+
+end
+

koans/code_mash.rb

@@ -1 +1 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')

koans/edgecase.rb

@@ -6,8 +6,24 @@ require 'test/unit/assertions'
 class FillMeInError < StandardError
 end
 
-def __(value="FILL ME IN")
-  value
+def in_ruby_version(version)
+  yield if RUBY_VERSION =~ /^#{version}/
+end
+
+def __(value="FILL ME IN", value19=:mu)
+  if RUBY_VERSION < "1.9"
+    value
+  else
+    (value19 == :mu) ? value : value19
+  end
+end
+
+def _n_(value=999999, value19=:mu)
+  if RUBY_VERSION < "1.9"
+    value
+  else
+    (value19 == :mu) ? value : value19
+  end
 end
 
 def ___(value=FillMeInError)
@@ -20,13 +36,56 @@ class Object
       self.send(method)
     end
   end
+
+  in_ruby_version("1.9") do
+    public :method_missing
+  end
 end
 
 module EdgeCase
+
+  module Color
+    #shamelessly stolen (and modified) from redgreen
+    COLORS = {
+      :clear   => 0,  :black   => 30, :red   => 31,
+      :green   => 32, :yellow  => 33, :blue  => 34,
+      :magenta => 35, :cyan    => 36,
+    }
+
+    module_function
+
+    COLORS.each do |color, value|
+      module_eval "def #{color}(string); colorize(string, #{value}); end"
+      module_function color
+    end
+
+    def colorize(string, color_value)
+      if ENV['NO_COLOR']
+        string
+      else
+        color(color_value) + string + color(COLORS[:clear])
+      end
+    end
+
+    def color(color_value)
+      "\e[#{color_value}m"
+    end
+  end
+
   class Sensei
     attr_reader :failure, :failed_test
 
-    AssertionError = Test::Unit::AssertionFailedError
+    in_ruby_version("1.8") do
+      AssertionError = Test::Unit::AssertionFailedError
+    end
+
+    in_ruby_version("1.9") do
+      if defined?(MiniTest)
+        AssertionError = MiniTest::Assertion
+      else
+        AssertionError = Test::Unit::AssertionFailedError
+      end
+    end
 
     def initialize
       @pass_count = 0
@@ -37,9 +96,9 @@ module EdgeCase
     def accumulate(test)
       if test.passed?
         @pass_count += 1
-        puts "  #{test.name} has expanded your awareness."
+        puts Color.green("  #{test.name} has expanded your awareness.")
       else
-        puts "  #{test.name} has damaged your karma."
+        puts Color.red("  #{test.name} has damaged your karma.")
         @failed_test = test
         @failure = test.failure
         throw :edgecase_exit
@@ -57,18 +116,19 @@ module EdgeCase
     def report
       if failed?
         puts
-        puts "You have not yet reached enlightenment ..."
-        puts failure.message
+        puts Color.green("You have not yet reached enlightenment ...")
+        puts Color.red(failure.message)
         puts
-        puts "Please meditate on the following code:"
+        puts Color.green("Please meditate on the following code:")
         if assert_failed?
-          puts find_interesting_lines(failure.backtrace)
+          #puts find_interesting_lines(failure.backtrace)
+          puts find_interesting_lines(failure.backtrace).collect {|l| Color.red(l) }
         else
-          puts failure.backtrace
+          puts Color.red(failure.backtrace)
         end
         puts
       end
-      say_something_zenlike
+      puts Color.green(a_zenlike_statement)
     end
 
     def find_interesting_lines(backtrace)
@@ -79,28 +139,29 @@ module EdgeCase
 
     # Hat's tip to Ara T. Howard for the zen statements from his
     # metakoans Ruby Quiz (http://rubyquiz.com/quiz67.html)
-    def say_something_zenlike
+    def a_zenlike_statement
       puts
       if !failed?
-        puts "Mountains are again merely mountains"
+        zen_statement =  "Mountains are again merely mountains"
       else
-        case (@pass_count % 10)
+        zen_statement = case (@pass_count % 10)
         when 0
-          puts "mountains are merely mountains"
+          "mountains are merely mountains"
         when 1, 2
-          puts "learn the rules so you know how to break them properly"
+          "learn the rules so you know how to break them properly"
         when 3, 4
-          puts "remember that silence is sometimes the best answer"
+          "remember that silence is sometimes the best answer"
         when 5, 6
-          puts "sleep is the best meditation"
+          "sleep is the best meditation"
         when 7, 8
-          puts "when you lose, don't lose the lesson"
+          "when you lose, don't lose the lesson"
         else
-          puts "things are not what they appear to be: nor are they otherwise"
+          "things are not what they appear to be: nor are they otherwise"
         end
       end
+      zen_statement
     end
-  end      
+  end
 
   class Koan
     include Test::Unit::Assertions
@@ -138,7 +199,7 @@ module EdgeCase
 
       def run_tests(accumulator)
         puts
-        puts "Thinking #{self}"
+        puts Color.green("Thinking #{self}")
         testmethods.each do |m|
           self.run_test(m, accumulator) if Koan.test_pattern =~ m.to_s
         end
@@ -149,12 +210,12 @@ module EdgeCase
         test.setup
         begin
           test.send(method)
-        rescue StandardError => ex
+        rescue StandardError, EdgeCase::Sensei::AssertionError => ex
           test.failed(ex)
         ensure
           begin
             test.teardown
-          rescue StandardError => ex
+          rescue StandardError, EdgeCase::Sensei::AssertionError => ex
             test.failed(ex) if test.passed?
           end
         end
@@ -177,7 +238,7 @@ module EdgeCase
               load(arg)
             else
               fail "Unknown command line argument '#{arg}'"
-            end              
+            end
           end
         end
       end

koans/path_to_enlightenment.rb

@@ -1,12 +1,16 @@
 # The path to Ruby Enlightenment starts with the following:
 
+$LOAD_PATH << File.dirname(__FILE__)
+
 require 'about_asserts'
 require 'about_nil'
 require 'about_arrays'
 require 'about_array_assignment'
 require 'about_hashes'
 require 'about_strings'
+require 'about_regular_expressions'
 require 'about_methods'
+require 'about_constants'
 require 'about_control_statements'
 require 'about_true_and_false'
 require 'about_triangle_project'

src/about_array_assignment.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutArrayAssignment < EdgeCase::Koan
   def test_non_parallel_assignment
@@ -35,4 +35,11 @@ class AboutArrayAssignment < EdgeCase::Koan
     assert_equal __("John"), first_name
   end
 
+  def test_swapping_with_parallel_assignment
+    first_name = "Roy"
+    last_name = "Rob"
+    first_name, last_name = last_name, first_name
+    assert_equal __('Rob'), first_name
+    assert_equal __('Roy'), last_name
+  end
 end

src/about_arrays.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutArrays < EdgeCase::Koan
   def test_creating_arrays

src/about_asserts.rb

@@ -1,7 +1,7 @@
 #!/usr/bin/env ruby
 # -*- ruby -*-
 
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutAsserts < EdgeCase::Koan
 

src/about_blocks.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutBlocks < EdgeCase::Koan
   def method_with_block

src/about_class_methods.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutClassMethods < EdgeCase::Koan
   class Dog
@@ -19,11 +19,11 @@ class AboutClassMethods < EdgeCase::Koan
 
   def test_objects_have_methods
     fido = Dog.new
-    assert_equal __(44), fido.methods.size
+    assert fido.methods.size > _n_(30)
   end
 
   def test_classes_have_methods
-    assert_equal __(79), Dog.methods.size
+    assert Dog.methods.size > _n_(40)
   end
 
   def test_you_can_define_methods_on_individual_objects

src/about_classes.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutClasses < EdgeCase::Koan
   class Dog
@@ -22,7 +22,7 @@ class AboutClasses < EdgeCase::Koan
     assert_equal __([]), fido.instance_variables
 
     fido.set_name("Fido")
-    assert_equal __(["@name"]), fido.instance_variables
+    assert_equal __(["@name"], [:@name]), fido.instance_variables
   end
 
   def test_instance_variables_cannot_be_accessed_outside_the_class
@@ -43,7 +43,7 @@ class AboutClasses < EdgeCase::Koan
     fido = Dog2.new
     fido.set_name("Fido")
 
-    assert_equal __("Fido"), fido.instance_variable_get("@name")    
+    assert_equal __("Fido"), fido.instance_variable_get("@name")
   end
 
   def test_you_can_rip_the_value_out_using_instance_eval
@@ -89,7 +89,7 @@ class AboutClasses < EdgeCase::Koan
 
     assert_equal __("Fido"), fido.name
   end
-  
+
   # ------------------------------------------------------------------
 
   class Dog5
@@ -125,7 +125,7 @@ class AboutClasses < EdgeCase::Koan
     # THINK ABOUT IT:
     # Why is this so?
   end
-  
+
   def test_different_objects_have_difference_instance_variables
     fido = Dog6.new("Fido")
     rover = Dog6.new("Rover")
@@ -180,11 +180,11 @@ class AboutClasses < EdgeCase::Koan
   def test_all_objects_support_to_s_and_inspect
     array = [1,2,3]
 
-    assert_equal __("123"), array.to_s
+    assert_equal __("123", "[1, 2, 3]"), array.to_s
     assert_equal __("[1, 2, 3]"), array.inspect
 
     assert_equal __("STRING"), "STRING".to_s
     assert_equal __('"STRING"'), "STRING".inspect
   end
- 
+
 end

src/about_constants.rb

@@ -0,0 +1,87 @@
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
+
+C = "top level"
+
+class AboutConstants < EdgeCase::Koan
+
+  C = "nested"
+
+  def test_nested_constants_may_also_be_referenced_with_relative_paths
+    assert_equal __("nested"), C
+  end
+
+  def test_top_level_constants_are_referenced_by_double_colons
+    assert_equal __("top level"), ::C
+  end
+
+  def test_nested_constants_are_referenced_by_their_complete_path
+    assert_equal __("nested"), AboutConstants::C
+    assert_equal __("nested"), ::AboutConstants::C
+  end
+
+  # ------------------------------------------------------------------
+
+  class Animal
+    LEGS = 4
+    def legs_in_animal
+      LEGS
+    end
+
+    class NestedAnimal
+      def legs_in_nested_animal
+        LEGS
+      end
+    end
+  end
+
+  def test_nested_classes_inherit_constants_from_enclosing_classes
+    assert_equal __(4), Animal::NestedAnimal.new.legs_in_nested_animal
+  end
+
+  # ------------------------------------------------------------------
+
+  class Reptile < Animal
+    def legs_in_reptile
+      LEGS
+    end
+  end
+
+  def test_subclasses_inherit_constants_from_parent_classes
+    assert_equal __(4), Reptile.new.legs_in_reptile
+  end
+
+  # ------------------------------------------------------------------
+
+  class MyAnimals
+    LEGS = 2
+
+    class Bird < Animal
+      def legs_in_bird
+        LEGS
+      end
+    end
+  end
+
+  def test_who_wins_with_both_nested_and_inherited_constants
+    assert_equal __(2), MyAnimals::Bird.new.legs_in_bird
+  end
+
+  # QUESTION: Which has precedence: The constant in the lexical scope,
+  # or the constant from the inheritance heirarachy?
+
+  # ------------------------------------------------------------------
+
+  class MyAnimals::Oyster < Animal
+    def legs_in_oyster
+      LEGS
+    end
+  end
+
+  def test_who_wins_with_explicit_scoping_on_class_definition
+    assert_equal __(4), MyAnimals::Oyster.new.legs_in_oyster
+  end
+
+  # QUESTION: Now Which has precedence: The constant in the lexical
+  # scope, or the constant from the inheritance heirarachy?  Why is it
+  # different than the previous answer?
+end

src/about_control_statements.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutControlStatements < EdgeCase::Koan
 
@@ -8,10 +8,10 @@ class AboutControlStatements < EdgeCase::Koan
     else
       result = :false_value
     end
-    assert_equal __, result
+    assert_equal __(:true_value), result
   end
 
-  def test_if_then_else_statements
+  def test_if_then_statements
     result = :default_value
     if true
       result = :true_value

src/about_dice_project.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class DiceSet
   attr_reader :values

src/about_exceptions.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutExceptions < EdgeCase::Koan
 

src/about_hashes.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutHashes < EdgeCase::Koan
   def test_creating_hashes
@@ -48,7 +48,7 @@ class AboutHashes < EdgeCase::Koan
 
   def test_hash_values
     hash = { :one => "uno", :two => "dos" }
-    assert_equal __(2), hash.keys.size
+    assert_equal __(2), hash.values.size
     assert_equal __(true), hash.values.include?("uno")
     assert_equal __(true), hash.values.include?("dos")
     assert_equal Array, hash.values.class

src/about_inheritance.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutInheritance < EdgeCase::Koan
   class Dog

src/about_iteration.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutIteration < EdgeCase::Koan
 

src/about_message_passing.rb

@@ -1,28 +1,28 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutMessagePassing < EdgeCase::Koan
-  
+
   class MessageCatcher
     def caught?
       true
     end
   end
-    
+
   def test_methods_can_be_called_directly
     mc = MessageCatcher.new
-    
-    assert mc.caught?    
+
+    assert mc.caught?
   end
-  
+
   def test_methods_can_be_invoked_by_sending_the_message
     mc = MessageCatcher.new
-    
+
     assert mc.send(:caught?)
   end
-  
+
   def test_methods_can_be_invoked_more_dynamically
     mc = MessageCatcher.new
-    
+
     assert mc.send("caught?")
     assert mc.send("caught" + __("?") )    # What do you need to add to the first string?
     assert mc.send("CAUGHT?".____(:downcase) )      # What would you need to do to the string?
@@ -40,23 +40,22 @@ class AboutMessagePassing < EdgeCase::Koan
 
   def test_classes_can_be_asked_if_they_know_how_to_respond
     mc = MessageCatcher.new
-    
+
     assert_equal __(true), mc.respond_to?(:caught?)
     assert_equal __(false), mc.respond_to?(:does_not_exist)
   end
-  
+
   # ------------------------------------------------------------------
 
   class MessageCatcher
     def add_a_payload(*args)
-      return :empty unless args
       args
     end
   end
-  
+
   def test_sending_a_message_with_arguments
     mc = MessageCatcher.new
-    
+
     assert_equal __([]), mc.add_a_payload
     assert_equal __([]), mc.send(:add_a_payload)
 
@@ -90,6 +89,18 @@ class AboutMessagePassing < EdgeCase::Koan
     #
     # If the method :method_missing causes the NoMethodError, then
     # what would happen if we redefine method_missing?
+    #
+    # NOTE:
+    #
+    # In Ruby 1.8 the method_missing method is public and can be
+    # called as shown above.  However, in Ruby 1.9 the method_missing
+    # method is private.  We explicitly made it public in the testing
+    # framework so this example works in both versions of Ruby.  Just
+    # keep in mind you can't call method_missing like that in Ruby
+    # 1.9. normally.
+    #
+    # Thanks.  We now return you to your regularly schedule Ruby
+    # Koans.
   end
 
   # ------------------------------------------------------------------

src/about_methods.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 def my_global_method(a,b)
   a + b
@@ -10,14 +10,14 @@ class AboutMethods < EdgeCase::Koan
     assert_equal __(5), my_global_method(2,3)
   end
 
-  def test_calling_global_methods_without_parenthesis
+  def test_calling_global_methods_without_parentheses
     result = my_global_method 2, 3
     assert_equal __(5), result
   end
 
   # (NOTE: We are Using eval below because the example code is
   # considered to be syntactically invalid).
-  def test_sometimes_missing_parenthesis_are_ambiguous
+  def test_sometimes_missing_parentheses_are_ambiguous
     #--
     eval "assert_equal 5, my_global_method(2, 3)" # REMOVE CHECK
     if false

src/about_modules.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutModules < EdgeCase::Koan
   module Nameable

src/about_nil.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutNil < EdgeCase::Koan
   def test_nil_is_an_object

src/about_open_classes.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutOpenClasses < EdgeCase::Koan
   class Dog

src/about_proxy_object_project.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 # Project: Create a Proxy Class
 #

src/about_regular_expressions.rb

@@ -0,0 +1,159 @@
+# -*- coding: utf-8 -*-
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
+
+class AboutRegularExpressions < EdgeCase::Koan
+  def test_a_pattern_is_a_regular_expression
+    assert_equal Regexp, /pattern/.class
+  end
+
+  def test_a_regexp_can_search_a_string_for_matching_content
+    assert_equal "match", "some matching content"[/match/]
+  end
+
+  def test_a_failed_match_returns_nil
+    assert_equal __(nil), "some matching content"[/missing/]
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_question_mark_means_optional
+    assert_equal __("ab"), "abbcccddddeeeee"[/ab?/]
+    assert_equal __("a"), "abbcccddddeeeee"[/az?/]
+  end
+
+  def test_plus_means_one_or_more
+    assert_equal __("bccc"), "abbcccddddeeeee"[/bc+/]
+  end
+
+  def test_asterisk_means_zero_or_more
+    assert_equal __("abb"), "abbcccddddeeeee"[/ab*/]
+    assert_equal __("a"), "abbcccddddeeeee"[/az*/]
+    assert_equal __(""), "abbcccddddeeeee"[/z*/]
+
+    # THINK ABOUT IT:
+    #
+    # When would * fail to match?
+  end
+
+  # THINK ABOUT IT:
+  #
+  # We say that the repetition operators above are "greedy."
+  #
+  # Why?
+
+  # ------------------------------------------------------------------
+
+  def test_the_left_most_match_wins
+    assert_equal __("a"), "abbccc az"[/az*/]
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_character_classes_give_options_for_a_character
+    animals = ["cat", "bat", "rat", "zat"]
+    assert_equal __(["cat", "bat", "rat"]), animals.select { |a| a[/[cbr]at/] }
+  end
+
+  def test_slash_d_is_a_shortcut_for_a_digit_character_class
+    assert_equal __("42"), "the number is 42"[/[0123456789]+/]
+    assert_equal __("42"), "the number is 42"[/\d+/]
+  end
+
+  def test_character_classes_can_include_ranges
+    assert_equal __("42"), "the number is 42"[/[0-9]+/]
+  end
+
+  def test_slash_s_is_a_shortcut_for_a_whitespace_character_class
+    assert_equal __(" \t\n"), "space: \t\n"[/\s+/]
+  end
+
+  def test_slash_w_is_a_shortcut_for_a_word_character_class
+    # NOTE:  This is more like how a programmer might define a word.
+    assert_equal __("variable_1"), "variable_1 = 42"[/[a-zA-Z0-9_]+/]
+    assert_equal __("variable_1"), "variable_1 = 42"[/\w+/]
+  end
+
+  def test_period_is_a_shortcut_for_any_non_newline_character
+    assert_equal __("abc"), "abc\n123"[/a.+/]
+  end
+
+  def test_a_character_class_can_be_negated
+    assert_equal __("the number is "), "the number is 42"[/[^0-9]+/]
+  end
+
+  def test_shortcut_character_classes_are_negated_with_capitals
+    assert_equal __("the number is "), "the number is 42"[/\D+/]
+    assert_equal __("space:"), "space: \t\n"[/\S+/]
+    assert_equal __(" = "), "variable_1 = 42"[/\W+/]
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_slash_a_anchors_to_the_start_of_the_string
+    assert_equal __("start"), "start end"[/\Astart/]
+    assert_equal __(nil), "start end"[/\Aend/]
+  end
+
+  def test_slash_z_anchors_to_the_end_of_the_string
+    assert_equal __("end"), "start end"[/end\z/]
+    assert_equal __(nil), "start end"[/start\z/]
+  end
+
+  def test_caret_anchors_to_the_start_of_lines
+    assert_equal __("2"), "num 42\n2 lines"[/^\d+/]
+  end
+
+  def test_dollar_sign_anchors_to_the_end_of_lines
+    assert_equal __("42"), "2 lines\nnum 42"[/\d+$/]
+  end
+
+  def test_slash_b_anchors_to_a_word_boundary
+    assert_equal __("vines"), "bovine vines"[/\bvine./]
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_parentheses_group_contents
+    assert_equal __("hahaha"), "ahahaha"[/(ha)+/]
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_parentheses_also_capture_matched_content_by_number
+    assert_equal __("Gray"), "Gray, James"[/(\w+), (\w+)/, 1]
+    assert_equal __("James"), "Gray, James"[/(\w+), (\w+)/, 2]
+  end
+
+  def test_variables_can_also_be_used_to_access_captures
+    assert_equal __("Gray, James"), "Name:  Gray, James"[/(\w+), (\w+)/]
+    assert_equal __("Gray"), $1
+    assert_equal __("James"), $2
+  end
+
+  # ------------------------------------------------------------------
+
+  def test_a_vertical_pipe_means_or
+    grays = /(James|Dana|Summer) Gray/
+    assert_equal __("James Gray"), "James Gray"[grays]
+    assert_equal __("Summer"), "Summer Gray"[grays, 1]
+    assert_equal __(nil), "Jim Gray"[grays, 1]
+  end
+
+  # THINK ABOUT IT:
+  #
+  # Explain the difference between a character class ([…]) and alternation (|).
+
+  # ------------------------------------------------------------------
+
+  def test_scan_is_like_find_all
+    assert_equal __(["one", "two", "three"]), "one two-three".scan(/\w+/)
+  end
+
+  def test_sub_is_like_find_and_replace
+    assert_equal __("one t-three"), "one two-three".sub(/(t\w*)/) { $1[0, 1] }
+  end
+
+  def test_gsub_is_like_find_and_replace_all
+    assert_equal __("one t-t"), "one two-three".gsub(/(t\w*)/) { $1[0, 1] }
+  end
+end

src/about_sandwich_code.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutUsingBlocks < EdgeCase::Koan
 

src/about_scope.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutScope < EdgeCase::Koan
   module Jims
@@ -28,7 +28,7 @@ class AboutScope < EdgeCase::Koan
     rover = Joes::Dog.new
     assert_equal __(:jims_dog), fido.identify
     assert_equal __(:joes_dog), rover.identify
-    
+
     assert_not_equal fido.class, rover.class
     assert_not_equal Jims::Dog, Joes::Dog
   end
@@ -41,7 +41,7 @@ class AboutScope < EdgeCase::Koan
   def test_bare_bones_class_names_assume_the_current_scope
     assert_equal __(true), AboutScope::String == String
   end
-  
+
   def test_nested_string_is_not_the_same_as_the_system_string
     assert_equal __(false), String == "HI".class
   end
@@ -73,7 +73,7 @@ class AboutScope < EdgeCase::Koan
   end
 
   def test_you_can_get_a_list_of_constants_for_any_class_or_module
-    assert_equal __(["Dog"]), Jims.constants
-    assert_equal __(122), Object.constants.size
+    assert_equal __(["Dog"], [:Dog]), Jims.constants
+    assert Object.constants.size > _n_(10)
   end
 end

src/about_scoring_project.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 # Greed is a dice game where you roll up to five dice to accumulate
 # points.  The following "score" function will be used calculate the

src/about_strings.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutStrings < EdgeCase::Koan
   def test_double_quoted_strings_are_strings
@@ -141,16 +141,25 @@ EOS
 
   def test_you_can_get_a_single_character_from_a_string
     string = "Bacon, lettuce and tomato"
-    assert_equal __(97), string[1]
+    assert_equal __(97, 'a'), string[1]
 
     # Surprised?
   end
 
-  def test_single_characters_are_represented_by_integers
-    assert_equal __(97), ?a
-    assert_equal __(true), ?a == 97
+  in_ruby_version("1.8") do
+    def test_in_ruby_1_8_single_characters_are_represented_by_integers
+      assert_equal __(97, 'a'), ?a
+      assert_equal __(true, false), ?a == 97
 
-    assert_equal __(true), ?b == (?a + 1)
+      assert_equal __(true), ?b == (?a + 1)
+    end
+  end
+
+  in_ruby_version("1.9") do
+    def test_in_ruby_1_9_single_characters_are_represented_by_strings
+      assert_equal __('a'), ?a
+      assert_equal __(false), ?a == 97
+    end
   end
 
   def test_strings_can_be_split
@@ -165,8 +174,8 @@ EOS
     assert_equal [__("the"), __("rain"), __("in"), __("spain")], words
 
     # NOTE: Patterns are formed from Regular Expressions.  Ruby has a
-    # very powerful Regular Expression library.  Unfortunately, time
-    # does not permit us to explore it in detail in Ruby 101.
+    # very powerful Regular Expression library.  We will become
+    # enlightened about them soon.
   end
 
   def test_strings_can_be_joined

src/about_triangle_project.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 # You need to write the triangle method in the file 'triangle.rb'
 require 'triangle.rb'

src/about_triangle_project_2.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 # You need to write the triangle method in the file 'triangle.rb'
 require 'triangle.rb'
@@ -9,6 +9,7 @@ class AboutTriangleAssignment2 < EdgeCase::Koan
   def test_illegal_triangles_throw_exceptions
     assert_raise(TriangleError) do triangle(0, 0, 0) end
     assert_raise(TriangleError) do triangle(3, 4, -5) end
+    assert_raise(TriangleError) do triangle(1, 1, 3) end
     assert_raise(TriangleError) do triangle(2, 4, 2) end 
  end
 end

src/about_true_and_false.rb

@@ -1,4 +1,4 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')
 
 class AboutTrueAndFalse < EdgeCase::Koan
   def truth_value(condition)

src/autotest/discover.rb

@@ -0,0 +1,3 @@
+Autotest.add_discovery do
+  "rubykoan" if File.exist? 'path_to_enlightenment.rb'
+end

src/autotest/rubykoan.rb

@@ -0,0 +1,24 @@
+require 'autotest'
+
+class Autotest::Rubykoan < Autotest
+  def initialize
+    super
+    @exceptions = /\.txt|Rakefile|\.rdoc/
+
+    self.order = :alpha
+    self.add_mapping(/^about_.*rb$/) do |filename, _|
+      filename
+    end 
+
+  end
+
+  def make_test_cmd files_to_test
+    "#{ruby}  'path_to_enlightenment.rb'"
+  end 
+
+  # quiet test/unit chatter
+  def handle_results(results)
+  end
+
+end
+

src/code_mash.rb

@@ -1 +1 @@
-require 'edgecase'
+require File.expand_path(File.dirname(__FILE__) + '/edgecase')

src/edgecase.rb

@@ -6,8 +6,24 @@ require 'test/unit/assertions'
 class FillMeInError < StandardError
 end
 
-def __(value="FILL ME IN")
-  value
+def in_ruby_version(version)
+  yield if RUBY_VERSION =~ /^#{version}/
+end
+
+def __(value="FILL ME IN", value19=:mu)
+  if RUBY_VERSION < "1.9"
+    value
+  else
+    (value19 == :mu) ? value : value19
+  end
+end
+
+def _n_(value=999999, value19=:mu)
+  if RUBY_VERSION < "1.9"
+    value
+  else
+    (value19 == :mu) ? value : value19
+  end
 end
 
 def ___(value=FillMeInError)
@@ -20,13 +36,56 @@ class Object
       self.send(method)
     end
   end
+
+  in_ruby_version("1.9") do
+    public :method_missing
+  end
 end
 
 module EdgeCase
+
+  module Color
+    #shamelessly stolen (and modified) from redgreen
+    COLORS = {
+      :clear   => 0,  :black   => 30, :red   => 31,
+      :green   => 32, :yellow  => 33, :blue  => 34,
+      :magenta => 35, :cyan    => 36,
+    }
+
+    module_function
+
+    COLORS.each do |color, value|
+      module_eval "def #{color}(string); colorize(string, #{value}); end"
+      module_function color
+    end
+
+    def colorize(string, color_value)
+      if ENV['NO_COLOR']
+        string
+      else
+        color(color_value) + string + color(COLORS[:clear])
+      end
+    end
+
+    def color(color_value)
+      "\e[#{color_value}m"
+    end
+  end
+
   class Sensei
     attr_reader :failure, :failed_test
 
-    AssertionError = Test::Unit::AssertionFailedError
+    in_ruby_version("1.8") do
+      AssertionError = Test::Unit::AssertionFailedError
+    end
+
+    in_ruby_version("1.9") do
+      if defined?(MiniTest)
+        AssertionError = MiniTest::Assertion
+      else
+        AssertionError = Test::Unit::AssertionFailedError
+      end
+    end
 
     def initialize
       @pass_count = 0
@@ -37,9 +96,9 @@ module EdgeCase
     def accumulate(test)
       if test.passed?
         @pass_count += 1
-        puts "  #{test.name} has expanded your awareness."
+        puts Color.green("  #{test.name} has expanded your awareness.")
       else
-        puts "  #{test.name} has damaged your karma."
+        puts Color.red("  #{test.name} has damaged your karma.")
         @failed_test = test
         @failure = test.failure
         throw :edgecase_exit
@@ -57,18 +116,19 @@ module EdgeCase
     def report
       if failed?
         puts
-        puts "You have not yet reached enlightenment ..."
-        puts failure.message
+        puts Color.green("You have not yet reached enlightenment ...")
+        puts Color.red(failure.message)
         puts
-        puts "Please meditate on the following code:"
+        puts Color.green("Please meditate on the following code:")
         if assert_failed?
-          puts find_interesting_lines(failure.backtrace)
+          #puts find_interesting_lines(failure.backtrace)
+          puts find_interesting_lines(failure.backtrace).collect {|l| Color.red(l) }
         else
-          puts failure.backtrace
+          puts Color.red(failure.backtrace)
         end
         puts
       end
-      say_something_zenlike
+      puts Color.green(a_zenlike_statement)
     end
 
     def find_interesting_lines(backtrace)
@@ -79,28 +139,29 @@ module EdgeCase
 
     # Hat's tip to Ara T. Howard for the zen statements from his
     # metakoans Ruby Quiz (http://rubyquiz.com/quiz67.html)
-    def say_something_zenlike
+    def a_zenlike_statement
       puts
       if !failed?
-        puts "Mountains are again merely mountains"
+        zen_statement =  "Mountains are again merely mountains"
       else
-        case (@pass_count % 10)
+        zen_statement = case (@pass_count % 10)
         when 0
-          puts "mountains are merely mountains"
+          "mountains are merely mountains"
         when 1, 2
-          puts "learn the rules so you know how to break them properly"
+          "learn the rules so you know how to break them properly"
         when 3, 4
-          puts "remember that silence is sometimes the best answer"
+          "remember that silence is sometimes the best answer"
         when 5, 6
-          puts "sleep is the best meditation"
+          "sleep is the best meditation"
         when 7, 8
-          puts "when you lose, don't lose the lesson"
+          "when you lose, don't lose the lesson"
         else
-          puts "things are not what they appear to be: nor are they otherwise"
+          "things are not what they appear to be: nor are they otherwise"
         end
       end
+      zen_statement
     end
-  end      
+  end
 
   class Koan
     include Test::Unit::Assertions
@@ -138,7 +199,7 @@ module EdgeCase
 
       def run_tests(accumulator)
         puts
-        puts "Thinking #{self}"
+        puts Color.green("Thinking #{self}")
         testmethods.each do |m|
           self.run_test(m, accumulator) if Koan.test_pattern =~ m.to_s
         end
@@ -149,12 +210,12 @@ module EdgeCase
         test.setup
         begin
           test.send(method)
-        rescue StandardError => ex
+        rescue StandardError, EdgeCase::Sensei::AssertionError => ex
           test.failed(ex)
         ensure
           begin
             test.teardown
-          rescue StandardError => ex
+          rescue StandardError, EdgeCase::Sensei::AssertionError => ex
             test.failed(ex) if test.passed?
           end
         end
@@ -177,7 +238,7 @@ module EdgeCase
               load(arg)
             else
               fail "Unknown command line argument '#{arg}'"
-            end              
+            end
           end
         end
       end

src/path_to_enlightenment.rb

@@ -1,12 +1,16 @@
 # The path to Ruby Enlightenment starts with the following:
 
+$LOAD_PATH << File.dirname(__FILE__)
+
 require 'about_asserts'
 require 'about_nil'
 require 'about_arrays'
 require 'about_array_assignment'
 require 'about_hashes'
 require 'about_strings'
+require 'about_regular_expressions'
 require 'about_methods'
+require 'about_constants'
 require 'about_control_statements'
 require 'about_true_and_false'
 require 'about_triangle_project'