3 The Ruby Koans walk you along the path to enlightenment in order to learn Ruby.
4 The goal is to learn the Ruby language, syntax, structure, and some common
5 functions and libraries. We also teach you culture. Testing is not just something we
6 pay lip service to, but something we live. It is essential in your quest to learn
7 and do great things in the language.
11 The koans are broken out into areas by file, hashes are covered in about_hashes.rb,
12 modules are introduced in about_modules.rb, etc. They are presented in order in the
13 path_to_enlightenment.rb file.
15 Each koan builds up your knowledge of Ruby and builds upon itself. It will stop at
16 the first place you need to correct.
18 Some koans simply need to have the correct answer substituted for an incorrect one.
19 Some, however, require you to supply your own answer. If you see the method +__+ (a
20 double underscore) listed, it is a hint to you to supply your own code in order to
21 make it work correctly.
25 If you do not have Ruby setup, please visit http://ruby-lang.org/en/downloads/ for
26 operating specific instructions. In order to run this you need ruby and rake
27 installed. To check the installations simply type:
29 *nix platforms from any terminal window:
34 Windows from the command prompt (cmd.exe)
39 If you don't have rake installed, just run `gem install rake`
41 Any response for Ruby with a version number greater than 1.8 is fine (should be
42 around 1.8.6 or more). Any version of rake will do.
44 == Generating the Koans
46 A fresh checkout will not include the koans, you will need to generate
49 [ruby_koans] $ rake gen # generates the koans directory
51 If you need to regenerate the koans, thus wiping your current `koans`,
53 [ruby_koans] $ rake regen # regenerates the koans directory, wiping the original
55 == The Path To Enlightenment
57 You can run the tests through rake or by calling the file itself (rake is the
58 recommended way to run them as we might build more functionality into this task).
60 *nix platforms, from the koans directory
62 [ruby_koans] $ rake # runs the default target :walk_the_path
63 [ruby_koans] $ ruby path_to_enlightenment.rb # simply call the file directly
65 Windows is the same thing
67 c:\ruby_koans\rake # runs the default target :walk_the_path
68 c:\ruby_koans\ruby path_to_enlightenment.rb # simply call the file directly
70 === Red, Green, Refactor
72 In test-driven development the mantra has always been, red, green, refactor. Write a
73 failing test and run it (red), make the test pass (green), then refactor it (that is
74 look at the code and see if you can make it any better). In this case you will need
75 to run the koan and see it fail (red), make the test pass (green), then take a
76 moment and reflect upon the test to see what it is teaching you and improve the
77 code to better communicate its intent (refactor).
79 The very first time you run it you will see the following output:
82 (in /Users/person/dev/ruby_koans)
83 /usr/bin/ruby1.8 path_to_enlightenment.rb
85 AboutAsserts#test_assert_truth has damaged your karma.
88 You have not yet reached enlightenment.
90 The answers you seek...
93 Please meditate on the following code:
94 ./about_asserts.rb:10:in `test_assert_truth'
95 path_to_enlightenment.rb:38:in `each_with_index'
96 path_to_enlightenment.rb:38
98 mountains are merely mountains
99 your path thus far [X_________________________________________________] 0/280
101 You have come to your first stage. If you notice it is telling you where to look for
104 Please meditate on the following code:
105 ./about_asserts.rb:10:in `test_assert_truth'
106 path_to_enlightenment.rb:38:in `each_with_index'
107 path_to_enlightenment.rb:38
109 We then open up the about_asserts.rb file and look at the first test:
111 # We shall contemplate truth by testing reality, via asserts.
112 def test_assert_truth
113 assert false # This should be true
116 We then change the +false+ to +true+ and run the test again. After you are
117 done, think about what you are learning. In this case, ignore everything except
118 the method name (+test_assert_truth+) and the parts inside the method (everything
121 In this case the goal is for you to see that if you pass a value to the +assert+
122 method, it will either ensure it is +true+ and continue on, or fail if in fact
123 the statement is +false+.
127 A special thanks to Mike Clark and Ara Howard for inspiring this
128 project. Mike Clark wrote an excellent blog post about learning Ruby
129 through unit testing. This sparked an idea that has taken a bit to
130 solidify, that of bringing new rubyists into the community through
131 testing. Ara Howard then gave us the idea for the Koans in his ruby
132 quiz entry on Meta Koans (a must for any rubyist wanting to improve
133 their skills). Also, "The Little Lisper" taught us all the value of
134 the short questions/simple answers style of learning.
136 Mike Clark's post :: http://www.clarkware.com/cgi/blosxom/2005/03/18
137 Meta Koans :: http://rubyquiz.com/quiz67.html
138 The Little Lisper :: http://www.amazon.com/Little-LISPer-Third-Daniel-Friedman/dp/0023397632
142 The Ruby Language :: http://ruby-lang.org
143 Try Ruby in your browser :: http://tryruby.org
145 Dave Thomas' introduction to Ruby Programming Ruby (the Pick Axe) :: http://pragprog.com/titles/ruby/programming-ruby
147 Brian Marick's fantastic guide for beginners Everyday Scripting with Ruby :: http://pragprog.com/titles/bmsft/everyday-scripting-with-ruby
151 Author :: Jim Weirich <jim@weirichhouse.org>
152 Author :: Joe O'Brien <joe@edgecase.com>
153 Issue Tracker :: http://www.pivotaltracker.com/projects/48111
154 Requires :: Ruby 1.8.x or later and Rake (any recent version)
158 http://i.creativecommons.org/l/by-nc-sa/3.0/88x31.png
160 RubyKoans is released under a Creative Commons,
161 Attribution-NonCommercial-ShareAlike, Version 3.0
162 (http://creativecommons.org/licenses/by-nc-sa/3.0/) License.