Paper::Money

Paper::Money gem helps with money conversion, comparison and arithmetic

# Configure the currency rates with respect to a base currency (here EUR):

Paper.configure(
  base_currency: 'EUR',
  conversion_rates: {
    'USD'     => 1.11,
    'Bitcoin' => 0.0047
  }
)

# Instantiate money objects:

fifty_eur = Paper::Money.new(50, 'EUR')

# Get amount and currency:

fifty_eur.amount   # => 50
fifty_eur.currency # => "EUR"
fifty_eur.inspect  # => "50.00 EUR"

# Convert to a different currency (should return a Money
# instance, not a String):

fifty_eur.convert_to('USD') # => 55.50 USD

# Perform operations in different currencies:

twenty_dollars = Paper::Money.new(20, 'USD')

# Arithmetics:

fifty_eur + twenty_dollars # => 68.02 EUR
fifty_eur - twenty_dollars # => 31.98 EUR
fifty_eur / 2              # => 25 EUR
twenty_dollars * 3         # => 60 USD

# Comparisons (also in different currencies):

twenty_dollars == Paper::Money.new(20, 'USD') # => true
twenty_dollars == Paper::Money.new(30, 'USD') # => false

fifty_eur_in_usd = fifty_eur.convert_to('USD')
fifty_eur_in_usd == fifty_eur          # => true

twenty_dollars > Paper::Money.new(5, 'USD')   # => true
twenty_dollars < fifty_eur             # => true

Installation

Add this line to your application's Gemfile:

gem 'paper_money'

And then execute:

$ bundle

Or install it yourself as:

$ gem install paper

Usage

TODO: Write usage instructions here

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/kukula/paper_money.