Contents

require 'bigdecimal'

class BigMoney
  VERSION = '0.1.0'
  
  class MoneyError < StandardError ; end
  class UncomparableCurrency < MoneyError ; end
  
  @@default_currency = :USD
  def self.default_currency ; @@default_currency ; end
  def self.default_currency=(c) ; @@default_currency = c ; end
  def default_currency ; self.class.default_currency ; end
  def default_currency=(c) ; self.class.default_currency = c ; end
  
  attr_reader :amount, :currency
  
  def initialize(amount, currency = nil)
    @amount = amount.class == BigDecimal ? amount : BigDecimal.new(amount.to_s)
    @currency = currency || self.default_currency
  end
  
  def eql?(other_money)
    currency == other_money.currency && amount == other_money.amount
  end
  
  def ==(other_money)
    eql?(other_money)
  end
  
  def <=>(other_money)
    raise UncomparableCurrency, "Cannot compare #{currency} to #{other_money.currency}" \
      unless currency == other_money.currency
    
    amount <=> other_money.amount
  end
  
  def -@
    BigMoney.new(-amount, currency)
  end
  
  def +(val)
    op(:+, val)
  end
  
  def -(val)
    op(:-, val)
  end
  
  def *(val)
    op(:*, val)
  end

  def /(val)
    op(:/, val)
  end
  
  def to_s
    to_formatted_s('%.2f')
  end
  
  def to_formatted_s(format)
    format.sub(/%s/, currency.to_s.upcase) % amount
  end
  
  def to_i
    amount.to_i
  end
  
  def to_f
    amount.to_f
  end

private
  def op(s, val)
    if val.class == BigMoney
      raise UncomparableCurrency, "Cannot compare #{currency} to #{val.currency}" \
        unless currency == val.currency
      BigMoney.new(amount.send(s, val.amount), currency)
    else
      BigMoney.new(amount.send(s, val), currency)
    end
  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
mroch-BigMoney-0.1.0	lib/big_money/big_money.rb