ruby challenge for y'all!

[Daniel Parker]

Hey guys, I was just playing around with ruby bindings this morning and came up with something very interesting:

class Pink

  attr_reader :color

  def initialize

    @color = "pink"

  end

  def pink?

    @color == "pink"

  end

end

class Blue

  def color

    "blue"

  end

  def import_method(name, other_object)

    (class << self; self end).send(:define_method, name, other_object.method(name).to_proc)

  end

end

# This produces very interesting results:

blue = Blue.new

pink = Pink.new

blue.import_method(:pink?, pink)

blue.color  #=> "blue"

blue.pink?  #=> true

What's happening is that (using a bit of black magic) the method "pink?" on the blue instance remains bound to the pink instance, so when you run blue.pink?, the result is that inside the "pink?" method, self is not blue, but pink!

Have fun with this! :)

- daniel parker -

"You have granted me life and steadfast love, and your care has preserved my spirit." Job 10:12
"The LORD is my chosen portion and my cup . . . indeed, I have a beautiful inheritance." Psalm 16:5-6
"Give what you can ... take nothing back!"