Implicts in Ruby, via Scala

gistfile1.rb

# Implicits in Ruby, based on Scala. Works like:
#
#  implicitly.from(BaseClass).to(WrapperClass).via do |base_object|
#    WrapperClass.new(base_object)
#  end
#
def implicitly
  Implicit.new
end

class Implicit
  def from(starting_class)
    @starting_class = starting_class
    try_to_do_everything
    self
  end

  def to(ending_class)
    @ending_class = ending_class
    try_to_do_everything
    self
  end

  def via(&transformer)
    @transformer = transformer
    try_to_do_everything
    self
  end

  def try_to_do_everything
    if !@starting_class.nil? && !@ending_class.nil? && [email protected]?
      transformer = @transformer
      (@ending_class.instance_methods-Object.instance_methods).each do |meth_name|
        @starting_class.class_eval do
          define_method(meth_name) do |*args|
            transformer.call(self).send(meth_name,*args)
          end
        end
      end
    end
  end
  private :try_to_do_everything
end

# For example ...

class FixnumWithTime
  def initialize(n)
    @n = n
  end

  def minutes
    seconds * 60
  end

  def hours
    minutes * 60
  end

  def seconds
    @n
  end
end

implicitly.from(Fixnum).to(FixnumWithTime).via {|n| FixnumWithTime.new(n) }

p 2.minutes
p 2.hours