From method redefinition to classless Ruby

Ruby
1

Hi list

Ara’s post about method redefinition was extremely rich intellectual
food, took some time to digest, but I just thought I share my findings
with you.

http://ruby-smalltalk.blogspot.com/

Cheers
Robert

2

On Aug 2, 4:43 pm, “Robert D.” [email protected] wrote:

Hi list

Ara’s post about method redefinition was extremely rich intellectual
food, took some time to digest, but I just thought I share my findings
with you.

Ara and Pit are impressive meta-coders indeed. Think Ara might even
have a Prototype lib
you’d enjoy.

BTW, if we were all good little scouts and always modularized our code
one could use:

class Module
# Prepend an “aspect” module to a module.
#
# module X
# def x; “x”; end
# end
#
# module U
# def x; ‘{’ + super + ‘}’; end
# end
#
# X.prepend U
#
# X.x # => “{x}”

def prepend( aspect )
  aspect.send(:include, self)
  extend aspect
end

end

Another trick for common injuns:

class Class

# Prepend an "aspect" module to a class.
#
# class Firetruck
#   def put_out_fire(option)
#     "Put out #{option}"
#   end
# end
#
# module FastFiretruck
#   def put_out_fire(option)
#     super("very #{option}!")
#   end
# end
#
# Firetruck.prepend(FastFiretruck)
#
# ft = Firetruck.new
# ft.put_out_fire('fast') #=> "Put out very fast!"

def prepend( aspect )
  _new      = method(:new)
  _allocate = method(:allocate)
  (class << self; self; end).class_eval do
    define_method(:new) do |*args|
      o = _new.call(*args)
      o.extend aspect
      o
    end
    define_method(:allocate) do |*args|
      o = _allocate.call(*args)
      o.extend aspect
      o
    end
  end
end

end

Albeit that has some unfortunate shortcomings.

T.

3

On 8/3/07, Trans [email protected] wrote:

have a Prototype lib
# end
aspect.send(:include, self)
# class Firetruck
#
o = _new.call(*args)

end

Albeit that has some unfortunate shortcomings.

T.
Well I do not really see these shortcomings, I’d love to have this
mail as a comment to my blogpost BTW, would you mind?

Concerning Ara’s Prototype library I have seen it flying by, I will
have a closer look, sure deserves an Exolink. But probably Ara’s had
all the fun for himself already and there is nothing left to do for me
:(.

Cheers
Robert

4

On Aug 3, 2:25 am, “Robert D.” [email protected] wrote:

#   module X

# Prepend an "aspect" module to a class.
#   end
  (class << self; self; end).class_eval do
  end
end

end

Albeit that has some unfortunate shortcomings.

T.

Well I do not really see these shortcomings, I’d love to have this
mail as a comment to my blogpost BTW, would you mind?

Go for it. The shortcoming in the later example are b/c it’s static
and not dynamic, ie. it happens at the time of instantiation. So it’s
not a simple thing to adjust on the fly. One could make it more
flexiable, but alas the Double Module Inclusion problem gets in the
way.

Concerning Ara’s Prototype library I have seen it flying by, I will
have a closer look, sure deserves an Exolink. But probably Ara’s had
all the fun for himself already and there is nothing left to do for me
:(.

Not at all, I think Ara’s been looking for Prototype allies :slight_smile: The
only problem with prototype.rb is that it’s so far removed for writing
ordinary Ruby, few are willing to embrace it --it’s almost like
writing in a different language.

T.

5

2007/8/2, Robert D. [email protected]:

Ara’s post about method redefinition was extremely rich intellectual
food, took some time to digest, but I just thought I share my findings
with you.

http://ruby-smalltalk.blogspot.com/

Robert, c’est très intéressant! I will keep your code and play a
little bit with it some time.

Regards,
Pit

6

On 8/4/07, Pit C. [email protected] wrote:

2007/8/2, Robert D. [email protected]:

Ara’s post about method redefinition was extremely rich intellectual
food, took some time to digest, but I just thought I share my findings
with you.

http://ruby-smalltalk.blogspot.com/

Robert, c’est très intéressant! I will keep your code and play a
little bit with it some time.

Merci, very kind of you, I am sure you are aware of the very basic
Object#deepdup, I am about to “fix” it…
it will become

Kernel#deepdup object, object_track={}

I guess you know what it will eventually do, it is the workerbee stuff
which is not interesting but has to be done :(.

Cheers
Robert