Class: Money

Inherits:
Object
  • Object
show all
Includes:
Comparable
Defined in:
lib/money/money.rb,
lib/money/errors.rb,
lib/money/exchange_bank.rb

Overview

bank.exchange(100_00, “USD”, “CAD”) # => 6450

Defined Under Namespace

Classes: ExchangeBank, UnknownRate

Constant Summary collapse

CURRENCIES = 
{
  "USD" => { :delimiter => ",", :separator => ".", :symbol => "$" },
  "CAD" => { :delimiter => ",", :separator => ".", :symbol => "$" },
  "HKD" => { :delimiter => ",", :separator => ".", :symbol => "$" },
  "SGD" => { :delimiter => ",", :separator => ".", :symbol => "$" },
  "BRL" => { :delimiter => ".", :separator => ",", :symbol => "R$" },
  "EUR" => { :delimiter => ",", :separator => ".", :symbol => '€', :html => '€' },
  "GBP" => { :delimiter => ",", :separator => ".", :symbol => '£', :html => '£' },
  "JPY" => { :delimiter => ".", :separator => ".", :symbol => '¥', :html => '¥' },
}

Class Attribute Summary collapse

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(cents, currency = nil, bank = nil) ⇒ Money

Creates a new money object.

Money.new(100)

Alternativly you can use the convinience methods like Money.ca_dollar and Money.us_dollar



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# File 'lib/money/money.rb', line 89

def initialize(cents, currency = nil, bank = nil)
  @cents = cents.to_i
  @currency = (currency || Money.default_currency).upcase
  @bank = bank || Money.default_bank
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(m, *x) ⇒ Object 



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# File 'lib/money/money.rb', line 322

def method_missing(m,*x)
  if m.to_s =~ /^as/
    exchange_to(m.to_s.split("_").last.upcase)
  else
    super
  end
end

Class Attribute Details

.default_bank ⇒ Object

Each Money object is associated to a bank object, which is responsible for currency exchange. This property allows one to specify the default bank object.

bank1 = MyBank.new
bank2 = MyOtherBank.new

Money.default_bank = bank1
money1 = Money.new(10)
money1.bank  # => bank1

Money.default_bank = bank2
money2 = Money.new(10)
money2.bank  # => bank2
money1.bank  # => bank1

The default value for this property is an instance if VariableExchangeBank. It allows one to specify custom exchange rates:

Money.default_bank.add_rate("USD", "CAD", 1.24515)
Money.default_bank.add_rate("CAD", "USD", 0.803115)
Money.us_dollar(100).exchange_to("CAD")  # => Money.ca_dollar(124)
Money.ca_dollar(100).exchange_to("USD")  # => Money.us_dollar(80)



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# File 'lib/money/money.rb', line 34

def default_bank
  @default_bank
end

.default_currency ⇒ Object

the default currency, which is used when Money.new is called without an explicit currency argument. The default value is “USD”.



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# File 'lib/money/money.rb', line 38

def default_currency
  @default_currency
end

Instance Attribute Details

#bank ⇒ Object (readonly)

Returns the value of attribute bank.



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# File 'lib/money/money.rb', line 7

def bank
  @bank
end

#cents ⇒ Object (readonly) Also known as: to_i

Returns the value of attribute cents.



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# File 'lib/money/money.rb', line 7

def cents
  @cents
end

#currency ⇒ Object (readonly)

Returns the value of attribute currency.



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# File 'lib/money/money.rb', line 7

def currency
  @currency
end

Class Method Details

.add_rate(*params) ⇒ Object 



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# File 'lib/money/money.rb', line 80

def self.add_rate(*params)
  Money.default_bank.add_rate(*params)
end

.ca_dollar(cents) ⇒ Object

Creates a new Money object of the given value, using the Canadian dollar currency.



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# File 'lib/money/money.rb', line 61

def self.ca_dollar(cents)
  Money.new(cents, "CAD")
end

.empty(currency = default_currency) ⇒ Object

Create a new money object with value 0.



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# File 'lib/money/money.rb', line 56

def self.empty(currency = default_currency)
  Money.new(0, currency)
end

.euro(cents) ⇒ Object

Creates a new Money object of the given value, using the Euro currency.



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# File 'lib/money/money.rb', line 71

def self.euro(cents)
  Money.new(cents, "EUR")
end

.real(cents) ⇒ Object

Creates a new Money object of the given value, using the Brazilian Real currency.



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# File 'lib/money/money.rb', line 76

def self.real(cents)
  Money.new(cents, "BRL")
end

.us_dollar(cents) ⇒ Object

Creates a new Money object of the given value, using the American dollar currency.



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# File 'lib/money/money.rb', line 66

def self.us_dollar(cents)
  Money.new(cents, "USD")
end

Instance Method Details

#%(fixnum) ⇒ Object 



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# File 'lib/money/money.rb', line 139

def %(fixnum)
  Money.new(cents % fixnum, currency)
end

#*(fixnum) ⇒ Object

multiply money by fixnum



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# File 'lib/money/money.rb', line 129

def *(fixnum)
  Money.new(cents * fixnum, currency)
end

#+(other_money) ⇒ Object 



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# File 'lib/money/money.rb', line 110

def +(other_money)
  other_money = Money.new(other_money) unless other_money.is_a? Money
  if currency == other_money.currency
    Money.new(cents + other_money.cents, other_money.currency)
  else
    Money.new(cents + other_money.exchange_to(currency).cents,currency)
  end
end

#-(other_money) ⇒ Object 



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# File 'lib/money/money.rb', line 119

def -(other_money)
  other_money = Money.new(other_money) unless other_money.is_a? Money
  if currency == other_money.currency
    Money.new(cents - other_money.cents, other_money.currency)
  else
    Money.new(cents - other_money.exchange_to(currency).cents, currency)
  end
end

#/(fixnum) ⇒ Object

divide money by fixnum check out split_in_installments method too



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# File 'lib/money/money.rb', line 135

def /(fixnum)
  Money.new(cents / fixnum, currency)
end

#<=>(other_money) ⇒ Object 



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# File 'lib/money/money.rb', line 101

def <=>(other_money)
  other_money = Money.new(other_money) unless other_money.is_a? Money
  if bank.same_currency?(currency, other_money.currency)
    cents <=> other_money.cents
  else
    cents <=> other_money.exchange_to(currency).cents
  end
end

#==(other_money) ⇒ Object

Do two money objects equal? Only works if both objects are of the same currency



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# File 'lib/money/money.rb', line 96

def ==(other_money)
  other_money.respond_to?(:cents) && cents == other_money.cents &&
    other_money.respond_to?(:currency) && bank.same_currency?(currency, other_money.currency)
end

#add_tax(tax) ⇒ Object

Just a helper if you got tax inputs in percentage. Ie. add_tax(20) => cents * 1.20



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# File 'lib/money/money.rb', line 190

def add_tax(tax)
  tax_breakdown(tax)[0]
end

#compound_interest(rate, count = 1, period = 12) ⇒ Object

Calculates compound interest Returns a money object with the sum of self + it



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# File 'lib/money/money.rb', line 150

def compound_interest(rate, count = 1, period = 12)
  Money.new(cents * ((1 + rate / 100.0 / period) ** count - 1))
end

#exchange_to(other_currency) ⇒ Object

Recieve the amount of this money object in another currency.



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# File 'lib/money/money.rb', line 313

def exchange_to(other_currency)
  Money.new(@bank.exchange(self.cents, currency, other_currency), other_currency)
end

#format(*rules) ⇒ Object

Format the price according to several rules Currently supported are :with_currency, :no_cents, :symbol and :html

with_currency:

Money.ca_dollar(0).format => "free"
Money.ca_dollar(100).format => "$1.00"
Money.ca_dollar(100).format(:with_currency => true) => "$1.00 CAD"
Money.us_dollar(85).format(:with_currency => true) => "$0.85 USD"

no_cents:

Money.ca_dollar(100).format(:no_cents) => "$1"
Money.ca_dollar(599).format(:no_cents) => "$5"

Money.ca_dollar(570).format(:no_cents, :with_currency) => "$5 CAD"
Money.ca_dollar(39000).format(:no_cents) => "$390"

symbol:

Money.new(100, :currency => "GBP").format(:symbol => "£") => "£1.00"

html:

Money.ca_dollar(570).format(:html => true, :with_currency => true) =>  "$5.70 <span class=\"currency\">CAD</span>"



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# File 'lib/money/money.rb', line 241

def format(*rules)
 # support for old format parameters
 rules = normalize_formatting_rules(rules)

 if cents == 0
   if rules[:display_free].respond_to?(:to_str)
     return rules[:display_free]
   elsif rules[:display_free]
     return "free"
   end
 end

 if rules.has_key?(:symbol)
   if rules[:symbol]
     symbol = rules[:symbol]
   else
     symbol = ""
   end
 else
   symbol = (CURRENCIES[currency] ? CURRENCIES[currency][:symbol] : "$")
 end
 self.currency

 delimiter = (CURRENCIES[currency] ? CURRENCIES[currency][:delimiter] : "," )
 separator = (CURRENCIES[currency] ? CURRENCIES[currency][:separator] : "." )

 if rules[:no_cents]
   formatted = sprintf("#{symbol}%d", cents.to_f / 100)
   formatted.gsub!(/(\d)(?=(\d\d\d)+(?!\d))/, "\\1#{delimiter}")
 else
   formatted = sprintf("#{symbol}%.2f", cents.to_f / 100).split('.')
   formatted[0].gsub!(/(\d)(?=(\d\d\d)+(?!\d))/, "\\1#{delimiter}")
   formatted = formatted.join(separator)
 end

 # Commify ("10000" => "10,000")
 formatted.gsub!(/(\d)(?=\d{3}+(?:\.|$))(\d{3}\..*)?/,'\1,\2')

 if rules[:with_currency]
   formatted << " "
   formatted << '<span class="currency">' if rules[:html]
   formatted << currency
   formatted << '</span>' if rules[:html]
 end
 formatted.gsub!(symbol,CURRENCIES[currency][:html]) if rules[:html]
 formatted
end

#in_installments_of(other_money, order = false) ⇒ Object

Split money in installments based on payment value

Money.new(1000_00).split_in_installments(Money.new(300_00))

> [ 334_00, 333_00, 333_00 ] (All Money instances)



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# File 'lib/money/money.rb', line 212

def in_installments_of(other_money, order=false)
  split_in_installments(cents/other_money.cents, order)
end

#normalize_formatting_rules(rules) ⇒ Object 



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# File 'lib/money/money.rb', line 289

def normalize_formatting_rules(rules)
  if rules.size == 1
    rules = rules.pop
    rules = { rules => true } if rules.is_a?(Symbol)
  else
    rules = rules.inject({}) do |h,s|
      h[s] = true
      h
    end
  end
  rules
end

#round_to_coin(coin) ⇒ Object

Round to nearest coin value basically, we don’t have coins for cents in CZK, our smallest fraction is 0.50CZK

Money.new(14_58).round_to_coin(50) => 14.50



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# File 'lib/money/money.rb', line 165

def round_to_coin(coin)
  coef = 1.0/coin
  val = (cents * coef).floor / coef
  Money.new(val, currency)
end

#simple_interest(rate, count = 1, period = 12) ⇒ Object

Calculate self + simple interest



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# File 'lib/money/money.rb', line 155

def simple_interest(rate, count = 1, period = 12)
  Money.new(rate / 100 / period * cents * count)
end

#split_in_installments(fixnum, order = false) ⇒ Object

Split money in number of installments

Money.new(10_00).split_in_installments(3)

> [ 3.34, 3.33, 3.33 ] (All Money instances)



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# File 'lib/money/money.rb', line 199

def split_in_installments(fixnum, order=false)
  wallet = Wallet.new(fixnum, Money.new(cents/fixnum,currency))
  to_add = cents % fixnum
  to_add.times { |m| wallet[m] += Money.new(1) }
  wallet.reverse! if order
  wallet
end

#tax_breakdown(tax) ⇒ Object

Returns array a where

a[0] is price _after_ applying tax (tax base)
a[1] is tax



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# File 'lib/money/money.rb', line 174

def tax_breakdown(tax)
  _tax = (cents * (tax / 100.0)).round
  [Money.new(cents + _tax, currency), Money.new(_tax, currency)]
end

#tax_reverse_breakdown(tax) ⇒ Object

Returns array a where a is price before applying tax (tax base) a is tax



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# File 'lib/money/money.rb', line 182

def tax_reverse_breakdown(tax)
  coef = tax/100.0
  [Money.new((cents / (1+coef)).round, currency),
   Money.new((cents*coef/(1+coef)).round, currency) ]
end

#to_f ⇒ Object

Money.ca_dollar(100).to_f => “1.0”



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# File 'lib/money/money.rb', line 308

def to_f
  cents / 100.0
end

#to_money ⇒ Object

Conversation to self



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# File 'lib/money/money.rb', line 318

def to_money
  self
end

#to_s ⇒ Object

Money.ca_dollar(100).to_s => “1.00”



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# File 'lib/money/money.rb', line 303

def to_s
  sprintf("%.2f", cents / 100.0)
end

#zero? ⇒ Boolean

Test if the money amount is zero

Returns:

  • (Boolean) 


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# File 'lib/money/money.rb', line 144

def zero?
  cents == 0
end