Class: Money::VariableExchangeBank

Inherits:
Object
  • Object
show all
Defined in:
lib/money/variable_exchange_bank.rb

Constant Summary collapse

@@singleton = 
VariableExchangeBank.new

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ VariableExchangeBank

Returns a new instance of VariableExchangeBank.



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# File 'lib/money/variable_exchange_bank.rb', line 29

def initialize
  @rates = {}
  @mutex = Mutex.new
end

Class Method Details

.instance ⇒ Object

Returns the singleton instance of VariableExchangeBank.

By default, Money.default_bank returns the same object.



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# File 'lib/money/variable_exchange_bank.rb', line 25

def self.instance
  @@singleton
end

Instance Method Details

#add_rate(from, to, rate) ⇒ Object

Registers a conversion rate. from and to are both currency names.



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# File 'lib/money/variable_exchange_bank.rb', line 35

def add_rate(from, to, rate)
  @mutex.synchronize do
    @rates["#{from}_TO_#{to}".upcase] = rate
  end
end

#exchange(cents, from_currency, to_currency) ⇒ Object

Exchange the given amount of cents in from_currency to to_currency. Returns the amount of cents in to_currency as an integer, rounded down.

If the conversion rate is unknown, then Money::UnknownRate will be raised.



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# File 'lib/money/variable_exchange_bank.rb', line 62

def exchange(cents, from_currency, to_currency)
  rate = get_rate(from_currency, to_currency)
  if !rate
    raise Money::UnknownRate, "No conversion rate known for '#{from_currency}' -> '#{to_currency}'"
  end
  (cents * rate).floor
end

#get_rate(from, to) ⇒ Object

Gets the rate for exchanging the currency named from to the currency named to. Returns nil if the rate is unknown.



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# File 'lib/money/variable_exchange_bank.rb', line 43

def get_rate(from, to)
  @mutex.synchronize do
    @rates["#{from}_TO_#{to}".upcase] 
  end
end

#same_currency?(currency1, currency2) ⇒ Boolean

Given two currency names, checks whether they’re both the same currency.

bank = VariableExchangeBank.new
bank.same_currency?("usd", "USD")   # => true
bank.same_currency?("usd", "EUR")   # => false

Returns:

  • (Boolean) 


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# File 'lib/money/variable_exchange_bank.rb', line 54

def same_currency?(currency1, currency2)
  currency1.upcase == currency2.upcase
end