require 'contextr'

# Horribly slow, proof-of-concept.

module NamespaceInjection
  def method_added(meth)
    super
    return  if meth.to_s =~ /^_.*_$/   # Don't fud

    ns = @namespace
    default.wrap meth do |n|
      ContextR.with_layers ns.layer do
        n.call_next
      end
    end
  end
end

class Class
  def namespace(name=nil, &block)
    layer :default  unless defined? default
    @namespace = ns = layer(:"namespace_#{name}")
    extend NamespaceInjection
    
    if block                    # Claim all methods defined inside to the ns.
      seen = []                 # now this is darn ugly
      (class << self; self; end).class_eval {
        _layer(:_ns_hackery_).post(:method_added) { |ne|
          meth = ne.arguments.first
          unless seen.include?(meth) || meth.to_s =~ /^_.*_$/
            seen << meth
            ns.claim meth
          end
        }
      }

      ContextR.with_layers :"_ns_hackery_" do
        class_eval &block
      end
    end
  end
end

class Array
  namespace :foo do  
    def mungle
      zip(reverse).flatten
    end
  end
end

class Foo
  namespace :foo

  def initialize
    p [1,2,3].mungle
  end
end


Foo.new

p [1,2,3].mungle  rescue p $!