Aggregation: problem with uninitialized composed_of object

rubyonrails-talk
1

Hi,

I'm getting this error:

p = Plan.new p.amount

TypeError: wrong argument type String (expected Fixnum)

Apparently this happens because the aggregation isn't initialized. Here's the code:

class Plan < ActiveRecord::Base     composed_of :amount,               :class_name => "Money",               :converter => Proc.new { |s| Money.new(s) },               :mapping => [:price, :value] end

class Money   attr_reader :value

  def initialize(string)     @value = BigDecimal(string.sub(/,/, '.'))   end

  def to_s     Integer(@value * 100).to_s.sub(/(\d{2})$/, ',\1')   end end

I would like to hide the aggregation from controllers...

There's the after_initialization callback where I could (try to) initialize the value object if it is nil...

I wonder what's the proper way to deal with this situation?

Thanks,

2

For the record...

TypeError: wrong argument type String (expected Fixnum)

[snip]

def initialize(string) @value = BigDecimal(string.sub(/,/, '.')) end

The problem was that value object can be initialized with a string (from the form) or with a number (from the db). Thus initialize should be changed, eg:

def initialize(value)   @value = BigDecimal(value.to_s(/,/, '.')) end