Module: Currency

Defined in:
lib/currency.rb,
lib/currency/currency_version.rb

Overview

Copyright © 2006-2007 Kurt Stephens <ruby-currency(at)umleta.com>

See LICENSE.txt for details.

Currency

The Currency package provides an object-oriented model of:

  • currencies

  • exchanges

  • exchange rates

  • exchange rate sources

  • monetary values

The core classes are:

  • Currency::Money - uses a scaled integer representation of a monetary value and performs accurate conversions to and from string values.

  • Currency::Currency - provides an object-oriented representation of a currency.

  • Currency::Exchange::Base - the base class for a currency exchange rate provider.

  • Currency::Exchange::Rate::Source::Base - the base class for an on-demand currency exchange rate data provider.

  • Currency::Exchange::Rate::Source::Provider - the base class for a bulk exchange rate data provider.

  • Currency::Exchange::Rate - represents a exchange rate between two currencies.

The example below uses Currency::Exchange::Xe to automatically get exchange rates from xe.com/ :

require 'currency'
require 'currency/exchange/rate/deriver'
require 'currency/exchange/rate/source/xe'
require 'currency/exchange/rate/source/timed_cache'

# Rate source initialization
provider = Currency::Exchange::Rate::Source::Xe.new
deriver  = Currency::Exchange::Rate::Deriver.new(:source => provider)
cache = Currency::Exchange::Rate::Source::TimedCache.new(:source => deriver)
Currency::Exchange::Rate::Source.default = cache

usd = Currency::Money('6.78', :USD)
puts "usd = #{usd.format}"
cad = usd.convert(:CAD)
puts "cad = #{cad.format}"

ActiveRecord Suppport

This package also contains ActiveRecord support for money values:

require 'currency'
require 'currency/active_record'

class Entry < ActiveRecord::Base
   money :amount
end

In the example above, the entries.amount database column is an INTEGER that represents US cents. The currency code of the money value can be stored in an additional database column or a default currency can be used.

Recent Enhancements

Storage and retrival of historical exchange rates

  • See Currency::Exchange::Rate::Source::Historical

  • See Currency::Exchange::Rate::Source::Historical::Writer

Automatic derivation of rates from base rates.

  • See Currency::Exchange::Rate::Deriver

Rate caching

  • See Currency::Exchange::Rate::Source::TimedCache

Rate Providers

  • See Currency::Exchange::Rate::Source::Xe

  • See Currency::Exchange::Rate::Source::NewYorkFed

  • See Currency::Exchange::Rate::Source::TheFinancials

Customizable formatting and parsing

  • See Currency::Formatter

  • See Currency::Parser

Future Enhancements

  • Support for inflationary rates within a currency, e.g. $10 USD in the year 1955 converted to 2006 USD.

SVN Repo

svn checkout svn://rubyforge.org/var/svn/currency/currency/trunk

Examples

See the examples/ and test/ directorys

Author

Kurt Stephens kurtstephens.com

Support

rubyforge.org/forum/forum.php?forum_id=7643

Copyright © 2006-2007 Kurt Stephens <ruby-currency(at)umleta.com>

See LICENSE.txt for details.

Defined Under Namespace

Modules: ActiveRecord, Exception, Exchange, Macro Classes: Config, Currency, Formatter, Money, Parser

Constant Summary collapse

CurrencyVersion = 
'0.5'

Class Method Summary collapse

Class Method Details

.Money(*opts) ⇒ Object

Use this function instead of Money#new:

Currency::Money("12.34", :CAD)

Do not do this:

Currency::Money.new("12.34", :CAD)

See Money#new.



120
121
122
 
# File 'lib/currency.rb', line 120

def self.Money(*opts)
  Money.new(*opts)
end