From: Eero Saynatkari <ruby-ml@...>
Date: 2005-12-12T13:20:23+09:00
Subject: Re: About class methods

On 2005.12.12 13:07, "jonathan <zjll9@imail.etsu.edu> <zjll9@ima"
<zjll9@imail.etsu.edu> wrote:
> unknown wrote:
> 
> > 
> >    class MyClass
> >    end
> > 
> >    def extend_class(classname)
> >      ex = Object.const_set(classname.to_s + "_extension", Class.new)
> >      ex.class_eval do
> >         def new_method1
> >           puts "new method"
> >         end
> >       end
> >    end
> > 
> >    extend_class(MyClass)
> >    x = MyClass_extension.new
> >    x.new_method1
> > 
> 
> Oh.  That's a neat way of doing it.  Would the code below also work in 
> order to support a dynamic method name?
> 
>     class MyClass
>     end
> 
>     def extend_class(classname, methodname)
>       ex = Object.const_set(classname.to_s + "_extension", Class.new)
>       ex.class_eval %{
>          def #(methodname)
>            puts "new method"
>          end }
>        end
>     end

Well, there is always define_method:

  # This code for illustrative purposes only. This is unadvisable.
  class Class
    def extend_by(method_name, &block)
      o = Object.const_set("#{self.name}Extension", Class.new(self))
      o.class_eval {
        define_method(method_name, &block)
      }
      o
    end
  end 

  class Foo
  end

  Extension = Foo.extend_by('quux') { puts "Hello from quux!" }
  Extension.new.quux

> --J

E