From: Gordon Thiesfeld <gthiesfeld@...>
Date: 2009-08-29T01:06:02+09:00
Subject: Re: Mass Assignment on Clas

On Fri, Aug 28, 2009 at 6:03 AM, Pete Moran<pete@zoborg.com> wrote:
> Hi there,
>
> I am a total newbie to Ruby, so please bare with me.
>
> I want to be able to be able to initialise a Class with a hash.  For
> instance If I have the class
>
> class Vehicle
>  attr_accessor :vtype, :description, :vehicle, :capacity
> end
>
> I want to be able to do
>
> Vehicle.new(:vtype => 'ECAR', :description => 'Great Car', :vehicle =>
> 'Ford Focus', :capacity => '10');
>
> Now I could do something like
>
> def initialize(items)
>     @vtype = items[:vtype]
>     @description = items[:description]
>     @vehicle = items[:vehicle]
>     @capacity = items[:capacity]
> #     puts items.inspect
>   end
>
> But I was wondering if there was a more generic way of doing this
> without specifically defining each variable in initialize? I think
> ActiveRecord does something similar!
>
> Many thanks for your assist!

Just playing devil's advocate, what about using OpenStruct?

require 'ostruct'

class Vehicle < OpenStruct

end

v1 = Vehicle.new(:vtype => 'ECAR', :description => 'Great Car', :vehicle =>
'Ford Focus', :capacity => '10')

I guess the concern would be the possibility of adding additional
accessors.  Using attr_accessor inside the class seems to keep me from
updating the variables.