From: 7stud -- <bbxx789_05ss@...>
Date: 2011-05-19T04:44:45+09:00
Subject: Re: Generating Functions in Ruby

Robert K. wrote in post #999483:
> On Wed, May 18, 2011 at 3:46 PM, Andreas Lundgren
> <andreas.lundgren.x@gmail.com> wrote:
>> return 5+4
>> I would like a way to generate the methods in runtime. As an old C-
>> SUM_TEMPLATE(OnePlusSeven, 1, 7)
>>
>> # Test program
>> puts("Five + Four is " + FivePlusFour().to_s)
>> puts("One + Seven is " + OnePlusSeven().to_s)
>>
>> Is this possible in Ruby?
>
> def SUM_TEMPLATE(name, x, y)
>   class <<self;self;end.class_eval "def #{name}; #{x} + #{y}; end"
> end
>

>> I need these functions to be class methods

...of what class?  Perhaps something like this:


def SUM_TEMPLATE(the_class, meth_name, x, y)
  class_obj = Object.const_get(the_class)

  class_obj.singleton_class.class_eval do
    define_method(meth_name) do
      x + y
    end
  end
end


class Dog
end

SUM_TEMPLATE('Dog', 'FivePlusFour', 5, 4)
puts Dog.FivePlusFour

--output:--
9

-- 
Posted via http://www.ruby-forum.com/.