Convenient CSV My solution for the homework assignment from the end of chapter 2 in the [Seven Languages in Seven Weeks](http://pragprog.com/book/btlang/seven-languages-in-seven-weeks) book

acts_as_csv.v1.rb

module ActsAsCsv
  def read
    @csv_contents = []
    filename = self.class.to_s.downcase + '.csv'
    file = File.new(filename)
    @headers = file.gets.chomp.split(', ')

    file.each do |row|
      @csv_contents << row.chomp.split(', ')
    end
  end

  def each
    csv_contents.each do |row|
      yield CsvRow.new(headers, row)
    end
  end

  attr_accessor :headers, :csv_contents
  def initialize
    read
  end
end

class CsvRow
  attr_reader :headers, :contents

  def initialize(headers,contents)
    @headers, @contents = headers, contents
  end

  def method_missing(*args)
    key = args.first.to_s
    idx = headers.index(key)
    contents[idx]
  end
end

acts_as_csv.v2.rb

module ActsAsCsv
  def read
    @csv_contents = []
    filename = self.class.to_s.downcase + '.csv'
    file = File.new(filename)
    @headers = file.gets.chomp.split(', ')

    file.each do |row|
      @csv_contents << row.chomp.split(', ')
    end
  end

  def each
    csv_contents.each do |row|
      yield row_struct.new(*row)
    end
  end

  attr_accessor :headers, :csv_contents
  def initialize
    read
  end

  private

  def row_struct
    @row_struct ||= Struct.new(*headers.map(&:to_sym))
  end
end

animals.csv

test.rb

require 'acts_as_csv'
class Animals
  include ActsAsCsv
end

animals = Animals.new

animals.each do |animal|
  puts "the #{animal.name} says #{animal.sound} right before he eats #{animal.eats}"
end

First thing I did was get rid of the whole self.included and ClassMethods thing from ActsAsCsv since it was only being used to include the instance methods which is what normally happens when you include a module anyway.

Then I wrote a class CsvRow as suggested in the book. But I thought the method_missing was a bit wonky.

So my acts_as_csv.v2.rb uses Struct to create its own little private class for the parsed csv class and then just inflates each row into an instance of that private class. I like that better.