How to Use
“Kagemusha\"
2007-09-29 Tatsuhiro Ujihisa
at Ruby Kansai Workshop#19
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✦ Tatsuhiro Ujihisa
✦ ruby, haskell, lisp, javascript
✦ Fuzzy Rough Sets Theory
✦ using ruby and haskell
✦ writer of Kagemusha README
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sorry for my not-good-English.
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Kagemusha
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What
✦ “Kagemusha is a library of
helper functions for testing
Ruby scripts.\"
-- Kagemusha README
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When
✦ making mock-class for tests
✦ modifying base-class with
scoped
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Who
✦ Yuya Kato
✦ My teacher of Ruby
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Are you a beginner or an
advanced rubyist?
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Advanced rubyists:
✦ Let's read source codes of
Kagemusha, without listening
this presentation.
✦ Enjoy Hacking!
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Beginners:
✦ Here we go.
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class Fixnum
def to_s
\"ujihisa\"
end
end
puts 23412
#=> ujihisa
Let's try on IRB
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Open Class
✦ global side-effects \"abc\"
:abc
#=>
#=>
1
nil
3 #=> \"a\"
3 + 5 #=> \"aa\"
etc...
It's crazy.
»Open Class with Scope?
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Kagemusha
require 'rubygems'
require 'kagemusha'
m = Kagemusha.new Fixnum
m.def :to_s do
\"ujihisa\"
end
m.swap do
# write what you want to do
puts 1
end
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class Fixnum
def to_s
\"ujihisa\"
end
end
require 'rubygems'
puts 23412 require 'kagemusha'
#=> ujihisa
m = Kagemusha.new Fixnum
m.def :to_s do
\"ujihisa\"
end
m.swap do
# write what you want to do
puts 1
end
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Remember these:
๏ requires
๏ Kagemusha.new
๏ Kagemusha#def, defs
๏ Kagemusha#swap
That's All.
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Demonstrate
✦ Kernel#rand, Time.now, etc.
✦ on Mac OSX, zsh, screen, vim,
ruby-1.8, Kagemusha-0.0.3
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Open Class Kagemusha
require 'rubygems'
require 'kagemusha'
class Fixnum m = Kagemusha.new Fixnum
def add(i) m.def :to_s do |i|
self + i self + i
end end
def self.add(i, j) m.defs :add do |i, j|
i + j
end
i + j
end
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✦ You can change/add any
methods in the block.
✦ You can write simple, safety
and clean code.
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Other styles
Kagemusha.new(A) do |m|
m.def(:f) {|c| puts c }
m.swap do
a = A.new
a.f 'blocked style'
end
end Kagemusha.new(A).
def(:f) {|c| puts c }.
swap do
a = A.new
a.f 'chained style'
end
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Default Mushas
✦ date, datetime, rand, time
require 'rubygems'
require 'kagemusha/rand' You have
only to
Kagemusha::Rand.always(1) do require these.
p rand(100)
p rand(100)
end
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Exercise
String#to_i returns 0
Fixnum#+ means minus
Hash#map returns not
array but hash
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That's all. Thank you!
Kagemusha
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