From: Farrel Lifson <farrel.lifson@...>
Date: 2006-09-17T21:36:28+09:00
Subject: Re: Why don't these writable atributes work?

On 17/09/06, Edward <edward@tanguay.info> wrote:
> Both of these code examples for making class properties don't work
> although they are pretty much straight out of the book "Programming
> Ruby". What I am doing wrong here?
>
> error is: undefined method `firstName' for #<User:0xb7f76b24
> @firstName="Newton"> (NoMethodError)
> ----------------------
> class User
>
>         attr_writer :firstName
>
>         def initialize(firstName)
>                 @firstName = firstName
>         end
> end
>
> user = User.new('Hal')
> user.firstName = 'Newton'
> print user.firstName
> --------------------------------
>
> class User
>
>         def firstName=(newFirstName)
>                 @firstName = newFirstName
>         end
>
>         def initialize(firstName)
>                 @firstName = firstName
>         end
> end
>
> user = User.new('Hal')
> user.firstName = 'Newton'
> print user.firstName
>
> --------------------------------
>
> Thanks,
>
> Edward Tanguay
> All my projects: http://www.tanguay.info
>
>
>

'attr_writer :firstName' only creates the 'firstName=' method just
like 'attr_reader :firstName' will only create the 'firstName' method.
What you need is 'attr_accessor :firstName' which creates both.

Farrel