Defining a method relative to a module's nesting

ruby-talk
1

module X
    def self.included(mod)
      define_method ... # define method from here
    end
  end

  module N
    # <- define method to this namespace (N)
    module M
      include X
    end
  end

T.

2

one way:

   harp:~ > cat a.rb
   module X
     def self::included other
       class << other
         eval <<-code
           def foo
             42
           end
         code
       end
       super
     end
   end

   module N
     module M
       include X
     end
   end

   p N::m::foo

   harp:~ > ruby a.rb
   42

nicer way:

   harp:~ > cat a.rb
   module X
     module ClassMethods
       def foo
         42
       end
     end
     module InstanceMethods
       def foo
         'forty-two'
       end
     end
     def self::included other
       other.module_eval{
         extend ClassMethods
         include InstanceMethods
       }
     end
   end

   class N
     class M
       include X
     end
   end

   p N::m::foo

   nm = N::m::new
   p nm.foo

   harp:~ > ruby a.rb
   42
   "forty-two"

kind regards.

-a

···

On Thu, 15 Sep 2005, Trans wrote:

module X
   def self.included(mod)
     define_method ... # define method from here
   end
end

module N
   # <- define method to this namespace (N)
   module M
     include X
   end
end

T.

--

email :: ara [dot] t [dot] howard [at] noaa [dot] gov
phone :: 303.497.6469
Your life dwells amoung the causes of death
Like a lamp standing in a strong breeze. --Nagarjuna

===============================================================================

3

batsman@tux-chan:~/src/ruby/ruby.head$ cat /tmp/fgdsdgdfg.rb
module X
  def self.included(mod)
    # for top-level module, parent = self; change for other semantics
    parent = Object.const_get(mod.to_s.sub(/::[^:]+\z/, ""))
    parent.send(:define_method, :foo){ puts "#{parent.to_s}#foo" } #fcall in 1.9
    class << parent; self end.send(:define_method, :bar) do #fcall in 1.9
      puts "#{parent.to_s}.bar"
    end
  end
end

module M
  module N
    include X
  end
end

Class.new{ include M }.new.foo
M.bar
batsman@tux-chan:~/src/ruby/ruby.head$ ruby /tmp/fgdsdgdfg.rb
M#foo
M.bar

···

On Thu, Sep 15, 2005 at 01:36:34PM +0900, Trans wrote:

  module X
    def self.included(mod)
      define_method ... # define method from here
    end
  end

  module N
    # <- define method to this namespace (N)
    module M
      include X
    end
  end

--
Mauricio Fernandez

4

Ara, I guess I did not explain well enough. Instead of

  p N::m::foo

I need

  p N::foo

T.

5

Mauricio,

That did the trick! Me thinks I will be generalizing the whole

  parent = Object.const_get(mod.to_s.sub(/::[^:]+\z/, ""))

thing in Nano.

Thanks,
T.

6

Oh,

#fcall in 1.9

I really hope not --an odd named meta-programming method. Please, I
beg, use #instance_send.

T.

7

    parent = Object.const_get(mod.to_s.sub(/::[^:]+\z/, ""))

      parent = Object.const_get(mod.name[/\w+/])

  ... should suit. [?]

8

class Module

  def nesting
    n = []
    name.split(/::/).inject(self){ |mod, name| c = mod.const_get(name)
; n << c ; c }
    return n
  end

end

9

I wrote:

> parent = Object.const_get(mod.to_s.sub(/::[^:]+\z/, ""))

      parent = Object.const_get(mod.name[/\w+/])

  ... should suit. [?]

Cuh! As soon as I hit the button -- my nonsense, sorry.

daz