From: "Ara.T.Howard" <ahoward@...>
Date: 2004-07-01T04:32:53+09:00
Subject: Re: [ANN] arrayfields-3.0.0

On Thu, 1 Jul 2004, Sean O'Dell wrote:

> Ara, any chance of getting arrayfields to not modify the Array methods but
> instead simply add an accessor to Array which returns an object that
> encapsulates this new functionality?
>
> So, instead of saying:
>
> row = ['bob', 30]
> row.fields = ['name', 'age']
> row['name'] #=> 'bob'
>
> you would say something like:
>
> row = ['bob', 30]
> row.arrayfields.fields = ['name', 'age']
> row.arrayfields['name'] #=> 'bob'
>
> My thinking is that if arrayfields functionality were contained in its own
> object that linked back to a parent array, you could create arrayfield
> objects and attach them to other "array-like" objects, such as database rows
> and so on.
>
> But also, it might prevent problems that arise later from taking over Array's
> methods where people want to use both arrayfields, and regular Array
> functionality.

well - theoretically you lose zero Array functionality since ArrayFields
methods are used if, and only if, the idx paramter is a String or Symbol which
would never be done with a normal Array.

that being said:

   jib:~/shared > cat a.rb
   require 'arrayfields'

   class FieldedArray
     attr :fieldset
     def initialize fields, array
       @a = array
       self.fields = fields
     end
     def method_missing(meth, *args, &block)
       @a.send(meth, *args, &block)
     end
     def fields= fields
       extend ArrayFields unless defined? @fieldset

       @fieldset =
         if ArrayFields::FieldSet === fields
           fields
         else
           ArrayFields::FieldSet.new fields
         end
     end
     attr_reader :fieldset
     def fields
       @fieldset and @fieldset.fields
     end
   end

   fa = FieldedArray.new %w(zero one two), [0, 1, 2]
   fa.each_with_field{|e, f| puts "#{ f } : #{ e }"}

   jib:~/shared > ruby a.rb
   zero : 0
   one : 1
   two : 2


i can't bloody believe that worked - go matz!

what'ya think of adding the above to 3.3.0 (along with gem spec)?

-a
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