From: "David A. Black" <dblack@...>
Date: 2007-09-25T21:44:44+09:00
Subject: Re: create a class in a class with eval

Hi --

On Tue, 25 Sep 2007, Gaspard Bucher wrote:

> I need to eval code that will create globally available classes. I tried this :
>
> class Test
>  def makeA
>    Module.send(:eval, "class A; end")
>    # same with: eval "class A; end"
>    puts Test.const_get('A') # => Test::A
>    puts Module.const_get('A') # => raise NameError, why ?
>  end
> end
>
> eval "class B; end"
> puts Module.const_get('B') # => B
>
> Test.new.makeA #=> bang

You could do:

   Module.module_eval "class A; end"

or (preferable, in my opinion):

   Module.const_set("A", Class.new)


David

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