From: Gavin Kistner <gavin@...>
Date: 2005-08-20T00:10:26+09:00
Subject: Re: Controlling acces to object instantiation?

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On Aug 19, 2005, at 9:03 AM, Andrew S. Townley wrote:
> The main issue here is that I want to prevent the client code from
> instantiating their own objects.  The objects should be created  
> only by
> a factory of some sort (who has implementation-specific configuration
> information about how to bootstrap them).


class Foo
     def self.make
         self.new( rand )
     end

     def initialize( id )
         @id = id
     end

     class << self
         protected :new
     end
end

p f1 = Foo.make
# => #<Foo:0x340858 @id=0.452814124524593>

p f2 = Foo.new( 12 )
# => /Users/gkistner/Desktop/tmp.rb:16: protected method `new' called  
for Foo:Class (NoMethodError)


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