class MoneyDt

Attributes

amount[R]

amount: Rational, currency: String

currency[R]

amount: Rational, currency: String

Public Class Methods

conversion_rates(base_currency, rates) click to toggle source

Example:

>> MoneyDt.conversion_rates("EUR", { "USD" => 1.11, "Bitcoin" => 0.0047 })

Arguments:

base_currency: String
rates: Hash

# File lib/money_dt/conversions.rb, line 11
def self.conversion_rates(base_currency, rates)
    @@conversion_rates[base_currency] ||= {}
    @@conversion_rates[base_currency].merge!(rates)
end

new(amount, currency) click to toggle source

Example:

>> fifty_eur = MoneyDt.new(50, "EUR") #=> <MoneyDt amount:50/1 currency:EUR>

Arguments:

amount: Fixnum, Float
currency: String

# File lib/money_dt.rb, line 12
def initialize(amount, currency)
    # The conversion to String is necessary as for a Float it isn't always valid to directly convert to Rational
    @amount = amount.to_s.to_r
    @currency = currency
end

Public Instance Methods

*(value) click to toggle source

Example:

>> MoneyDt.new(10, "USD") * 2 #=> <MoneyDt amount:20/1, currency:USD>

Arguments:

value: Fixnum, Float

# File lib/money_dt/arithmetics.rb, line 51
def *(value)
    MoneyDt.new(self.amount * value, self.currency)
end

+(another) click to toggle source

Example:

>> MoneyDt.conversion_rates("EUR", { "USD" => 1.10 })
>> MoneyDt.new(10, "EUR") + MoneyDt.new(10, "USD") #=> <MoneyDt amount:1909/100, currency:EUR>

Arguments:

another: MoneyDt

# File lib/money_dt/arithmetics.rb, line 10
def +(another)
    if self.currency == another.currency
        MoneyDt.new(self.amount + another.amount, self.currency)
    else
        another_converted = another.convert_to(self.currency)
        MoneyDt.new(self.amount + another_converted.amount, self.currency)
    end
end

-(another) click to toggle source

Example:

>> MoneyDt.conversion_rates("EUR", { "USD" => 1.10 })
>> MoneyDt.new(10, "EUR") - MoneyDt.new(10, "USD") #=> <MoneyDt amount:91/100, currency:EUR>

Arguments:

another: MoneyDt

# File lib/money_dt/arithmetics.rb, line 26
def -(another)
    if self.currency == another.currency
        MoneyDt.new(self.amount - another.amount, self.currency)
    else
        another_converted = another.convert_to(self.currency)
        MoneyDt.new(self.amount - another_converted.amount, self.currency)
    end
end

/(value) click to toggle source

Example:

>> MoneyDt.new(10, "USD") / 2 #=> <MoneyDt amount:5/1, currency:USD>

Arguments:

value: Fixnum, Float

# File lib/money_dt/arithmetics.rb, line 41
def /(value)
    MoneyDt.new(self.amount / value, self.currency)
end

<=>(another) click to toggle source

Two MoneyDt objects are compared on the basis of their amount up to the cents

Arguments:

another: MoneyDt

# File lib/money_dt/comparisons.rb, line 9
def <=>(another)
    if self.currency == another.currency
        self.amount.round(2) <=> another.amount.round(2)
    else
        another_converted = another.convert_to(self.currency)
        self.amount.round(2) <=> another_converted.amount.round(2)
    end
end

convert_to(new_currency) click to toggle source

Example:

>> MoneyDt.conversion_rates("EUR", { "USD" => 1.11, "Bitcoin" => 0.0047 })
>> fifty_eur = MoneyDt.new(50, "EUR")
>> fifty_eur.convert_to("USD") #=> <MoneyDt amount:555/10, currency:USD>

Arguments:

new_currency: String

# File lib/money_dt/conversions.rb, line 24
def convert_to(new_currency)
    if @@conversion_rates[self.currency] && (rate = @@conversion_rates[self.currency][new_currency])
        # When converting to a base currency (rates are based on it)
        MoneyDt.new(self.amount * rate, new_currency)
    elsif @@conversion_rates[new_currency] && (rate = @@conversion_rates[new_currency][self.currency])
        # When converting to another currency (rates aren't based on it)
        MoneyDt.new(self.amount * (1 / rate), new_currency)
    end
end

inspect() click to toggle source

Example:

>> fifty_eur = MoneyDt.new(50, "EUR")
>> fifty_eur.inspect #=> "50.00 EUR"

# File lib/money_dt.rb, line 22
def inspect
    "#{'%.2f' % amount} #{currency}"
end