From: Josh Cheek <josh.cheek@...>
Date: 2011-01-29T05:53:32+09:00
Subject: Re: instantiating a class

--0016361e847c298b6e049aee427e
Content-Type: text/plain; charset=ISO-8859-1

On Fri, Jan 28, 2011 at 2:39 PM, Rick Tan <bellcolt@hotmail.com> wrote:

> How do i instantiate a class whose name is contained in a variable ?
>
> For example
>
>  Class myClass
>  end
>
>  myVariable="myClass"
>
> So basically i like to use the content of myVariable to dictate which
> class to instantiate, i.e. doing the same thing as myClass.new but let
> myVariable determines which class i instantiate.
>
> Thanks in advance
>
> --
> Posted via http://www.ruby-forum.com/.
>
>
class MyClass
end

class_name = 'MyClass'
klass = Kernel.const_get(class_name) # => MyClass
klass.new # => #<MyClass:0x41753c>



Note that this doesn't work if your class is namespaced by a module or other
class. If that is the case, you'll have to look up older discussions on the
topic, or use something like ActiveSupport's constantize

require 'active_support'

module MyMod
  class MyClass
  end
end

class_name = 'MyMod::MyClass'
klass = class_name.constantize # => MyMod::MyClass
klass.new # => #<MyMod::MyClass:0x49f0c4>

--0016361e847c298b6e049aee427e--