sample_a.sc.rb

class Sample

  def hello name
    # sc
  end

  def sum n1, n2
    # sc sum n1, n2
  end

  def rule_of_three a, b, c
    # sc multiply c, b {|x| divide x, a }
  end

end

__END__
sc hello String -> String
  "Minion"  -> "Say Hello to Minion"
  "Roberto" -> "Say Hello to Roberto"
  "Roland"  -> "Say Hello to Roland"

sc sum Fixnum, Fixnum -> Fixnum
  1, 1 -> 2
  1, 2 -> 3
  2, 2 -> 4

sc multiply Float, Float -> Float
  1.0, 1.0 -> 1.0
  1.0, 2.0 -> 2.0
  2.0, 2.0 -> 4.0

sc divide Float, Float -> Float
  1.0, 1.0 -> 1.0
  2.0, 1.0 -> 2.0
  2.0, 2.0 -> 1.0

sample_b.rb

class Sample

  include SC

  implements hello: :name

  implements \
    sum: [:n1, :n2], 
    rule_of_three: [:a, :b, :c]

  def double n1
    self.sum(n1, n1)
  end

end

__END__
spec_for hello String -> String
  "Minion"  -> "Say Hello to Minion"
  "Roberto" -> "Say Hello to Roberto"
  "Roland"  -> "Say Hello to Roland"

spec_for sum Fixnum, Fixnum -> Fixnum
  1, 1 -> 2
  1, 2 -> 3
  2, 2 -> 4

spec_for rule_of_three Float, Float, Float -> Float
  1.0, 1.0, 2.0  -> 2.0
  2.0, 4.0, 3.0  -> 6.0
  10.0, 2.0, 3.0 -> 0.6

sample_c.rb

class Sample

  include SC

  implements hello: :name

  implements \
    sum: [:n1, :n2], 
    rule_of_three: [:a, :b, :c]

  def double n1
    self.sum(n1, n1)
  end

end

sample_spec.rb

describe Sample do
 
  cs_spec_for '#hello String -> String' do 
    sample.hello('Minion').should == 'Say Hello to Minion'
    sample.hello('Roberto').should == 'Say Hello to Roberto'
    sample.hello('Roland').should == 'Say Hello to Roland'
  end

  cs_spec_for '#sum Fixnum, Fixnum -> Fixnum' do
    sample.sum(1, 1).should == 2
    sample.sum(1, 2).should == 3
    sample.sum(2, 2).should == 4
  end

  cd_spec_for '#rule_of_three Float, Float, Float -> Float' do
    sample.rule_of_three(1.0, 1.0, 2.0).should == 2.0
    sample.rule_of_three(2.0, 4.0, 3.0).should == 6.0
    sample.rule_of_three(10.0, 2.0, 3.0).should == 0.6
  end

end