From: jos@... (Jos Backus)
Date: 2002-06-07T08:33:34+09:00
Subject: Re: Returning an instance from a different class from new

In article <20020606205418.GA4313@digikata.com>,
Alan Chen  <alan@digikata.com> wrote:
>I would recommend breaking out the functionality in
>Foo's initialize into a factory function.

Thanks, I understand this example (I think):

module FooFactory
  def build(sel, field)
    case sel
    when "1"
      return Bar.new(field)
    when "2"
      return Baz.new(field)
    end
  end
end

include FooFactory

class Foo
  attr_accessor :field
  def initialize(field)
    @field = field
  end
end

class Bar < Foo
  def initialize(field)
    super
  end
end

class Baz < Foo
  def initialize(field)
    super
  end
end

o = FooFactory.build('1', "field1")
p o.type, o.field
o = FooFactory.build('2', "field2")
p o.type, o.field

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