Class: Money

Inherits:
Object
  • Object
show all
Extended by:
Constructors
Includes:
Comparable, Arithmetic
Defined in:
lib/money/money.rb,
lib/money/version.rb,
lib/money/currency.rb,
lib/money/bank/base.rb,
lib/money/currency/loader.rb,
lib/money/money/formatter.rb,
lib/money/money/allocation.rb,
lib/money/money/arithmetic.rb,
lib/money/money/constructors.rb,
lib/money/rates_store/memory.rb,
lib/money/currency/heuristics.rb,
lib/money/locale_backend/base.rb,
lib/money/locale_backend/i18n.rb,
lib/money/bank/single_currency.rb,
lib/money/money/locale_backend.rb,
lib/money/locale_backend/errors.rb,
lib/money/bank/variable_exchange.rb,
lib/money/money/formatting_rules.rb,
lib/money/locale_backend/currency.rb

Overview

"Money is any object or record that is generally accepted as payment for goods and services and repayment of debts in a given socio-economic context or country." -Wikipedia

An instance of Money represents an amount of a specific currency.

Money is a value object and should be treated as immutable.

See Also:

Defined Under Namespace

Modules: Arithmetic, Bank, Constructors, LocaleBackend, RatesStore Classes: Allocation, Currency, Formatter, FormattingRules, UndefinedSmallestDenomination

Constant Summary collapse

VERSION = 
'7.0.0'.freeze

Class Attribute Summary collapse

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Constructors

ca_dollar, empty, euro, pound_sterling, us_dollar

Methods included from Arithmetic

#%, #*, #+, #-, #-@, #/, #<=>, #==, #abs, #coerce, #div, #divmod, #eql?, #modulo, #negative?, #nonzero?, #positive?, #remainder, #zero?

Constructor Details

#initialize(obj, currency = nil, options = {}) ⇒ Money

Creates a new Money object of value given in the +fractional unit+ of the given +currency+.

Alternatively you can use the convenience methods like Money::Constructors#ca_dollar and Money::Constructors#us_dollar.

Examples:

Money.new(100)        #=> #<Money @fractional=100 @currency="USD">
Money.new(100, "USD") #=> #<Money @fractional=100 @currency="USD">
Money.new(100, "EUR") #=> #<Money @fractional=100 @currency="EUR">

Parameters:

  • obj (Object) —

    Either the fractional value of the money, a Money object, or a currency. (If passed a currency as the first argument, a Money will be created in that currency with fractional value = 0.

  • currency (Currency, String, Symbol) (defaults to: nil) —

    The currency format.

  • options (Hash) (defaults to: {}) —

    Optional settings for the new Money instance

  • [Money::Bank::*] (Hash) —

    a customizable set of options

Raises:

  • (ArgumentError) 


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# File 'lib/money/money.rb', line 363

def initialize(obj, currency = nil, options = {})
  # For backwards compatibility, if options is not a Hash, treat it as a bank parameter
  unless options.is_a?(Hash)
    options = { bank: options }
  end

  @fractional = as_d(obj.respond_to?(:fractional) ? obj.fractional : obj)
  @currency   = obj.respond_to?(:currency) ? obj.currency : Currency.wrap(currency)
  @currency ||= Money.default_currency
  @bank       = obj.respond_to?(:bank) ? obj.bank : options[:bank]
  @bank     ||= Money.default_bank

  # BigDecimal can be Infinity and NaN, money of that amount does not make sense
  raise ArgumentError, 'must be initialized with a finite value' unless @fractional.finite?
  raise Currency::NoCurrency, 'must provide a currency' if @currency.nil?
end

Class Attribute Details

.conversion_precision ⇒ Integer

Used to specify precision for converting Rational to BigDecimal

Returns:

  • (Integer) 


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# File 'lib/money/money.rb', line 161

attr_accessor :default_formatting_rules,
:default_infinite_precision,
:conversion_precision,
:strict_eql_compare

.default_bank ⇒ Object

Modified to support thread-local bank override



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# File 'lib/money/money.rb', line 161

attr_accessor :default_formatting_rules,
:default_infinite_precision,
:conversion_precision,
:strict_eql_compare

.default_formatting_rules ⇒ Hash

Used to define a default hash of rules for every time +Money#format+ is called. Rules provided on method call will be merged with the default ones. To overwrite a rule, just provide the intended value while calling +format+.

Examples:

Money.default_formatting_rules = { display_free: true }
Money.new(0, "USD").format                          # => "free"
Money.new(0, "USD").format(display_free: false)  # => "$0.00"

Returns:

  • (Hash)

See Also:



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# File 'lib/money/money.rb', line 161

def default_formatting_rules
  @default_formatting_rules
end

.default_infinite_precision ⇒ Boolean

Returns Use this to enable infinite precision cents as the global default.

Returns:

  • (Boolean) —

    Use this to enable infinite precision cents as the global default



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# File 'lib/money/money.rb', line 161

attr_accessor :default_formatting_rules,
:default_infinite_precision,
:conversion_precision,
:strict_eql_compare

.locale_backend ⇒ Object

Returns the value of attribute locale_backend.



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

def locale_backend
  @locale_backend
end

.strict_eql_compare ⇒ Boolean

Use this to specify how +Money#eql?+ behaves. Opt-in to the new behavior by setting this to +true+ and disable warnings when comparing zero amounts with different currencies.

Examples:

Money.strict_eql_compare = false # (default)
Money.new(0, "USD").eql?(Money.new(0, "EUR")) # => true
# => [DEPRECATION] warning

Money.strict_eql_compare = true
Money.new(0, "USD").eql?(Money.new(0, "EUR")) # => false

Returns:

  • (Boolean)

See Also:

  • #eql


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# File 'lib/money/money.rb', line 161

attr_accessor :default_formatting_rules,
:default_infinite_precision,
:conversion_precision,
:strict_eql_compare

Instance Attribute Details

#bank ⇒ Object (readonly)

Returns the value of attribute bank.



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# File 'lib/money/money.rb', line 105

attr_reader :currency, :bank

#currency ⇒ Currency (readonly)

Returns The money's currency.

Returns:



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# File 'lib/money/money.rb', line 105

def currency
  @currency
end

#default_currency ⇒ Money::Currency

Returns The default currency, which is used when +Money.new+ is called without an explicit currency argument.

Returns:

  • (Money::Currency) —

    The default currency, which is used when +Money.new+ is called without an explicit currency argument.



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# File 'lib/money/money.rb', line 172

def self.default_currency
  if @default_currency.nil?
    nil
  elsif @default_currency.respond_to?(:call)
    Money::Currency.new(@default_currency.call)
  else
    Money::Currency.new(@default_currency)
  end
end

Class Method Details

.add_rate(from_currency, to_currency, rate) ⇒ Numeric

Adds a new exchange rate to the default bank and return the rate.

Examples:

Money.add_rate("USD", "CAD", 1.25) #=> 1.25

Parameters:

  • from_currency (Currency, String, Symbol) —

    Currency to exchange from.

  • to_currency (Currency, String, Symbol) —

    Currency to exchange to.

  • rate (Numeric) —

    Rate to exchange with.

Returns:

  • (Numeric) 


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# File 'lib/money/money.rb', line 293

def self.add_rate(from_currency, to_currency, rate)
  Money.default_bank.add_rate(from_currency, to_currency, rate)
end

.default_currency ⇒ Object 



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# File 'lib/money/money.rb', line 172

def self.default_currency
  if @default_currency.nil?
    nil
  elsif @default_currency.respond_to?(:call)
    Money::Currency.new(@default_currency.call)
  else
    Money::Currency.new(@default_currency)
  end
end

.default_currency=(currency) ⇒ Object 



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

def self.default_currency=(currency)
  @default_currency = currency
end

.disallow_currency_conversion! ⇒ Object

Sets the default bank to be a SingleCurrency bank that raises on currency exchange. Useful when apps operate in a single currency at a time.



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# File 'lib/money/money.rb', line 299

def self.disallow_currency_conversion!
  self.default_bank = Bank::SingleCurrency.instance
end

.from_amount(amount, currency = default_currency, options = {}) ⇒ Money

Creates a new Money object of value given in the +unit+ of the given +currency+.

Examples:

Money.from_amount(23.45, "USD") # => #<Money fractional:2345 currency:USD>
Money.from_amount(23.45, "JPY") # => #<Money fractional:23 currency:JPY>

Parameters:

  • amount (Numeric) —

    The numerical value of the money.

  • currency (Currency, String, Symbol) (defaults to: default_currency) —

    The currency format.

  • options (Hash) (defaults to: {}) —

    Optional settings for the new Money instance

  • [Money::Bank::*] (Hash) —

    a customizable set of options

Returns:

Raises:

  • (ArgumentError)

See Also:



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

def self.from_amount(amount, currency = default_currency, options = {})
  raise ArgumentError, "'amount' must be numeric" unless Numeric === amount

  currency = Currency.wrap(currency) || Money.default_currency
  raise Currency::NoCurrency, 'must provide a currency' if currency.nil?

  value = amount.to_d * currency.subunit_to_unit
  new(value, currency, options)
end

.from_dollars(amount, currency = default_currency, options = {}) ⇒ Object

DEPRECATED.

See Also:



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# File 'lib/money/money.rb', line 331

def self.from_dollars(amount, currency = default_currency, options = {})
  warn "[DEPRECATION] `Money.from_dollars` is deprecated in favor of " \
       "`Money.from_amount`."

  from_amount(amount, currency, options)
end

.inherited(base) ⇒ Object 



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# File 'lib/money/money.rb', line 247

def self.inherited(base)
  base.setup_defaults
end

.rounding_mode ⇒ BigDecimal::ROUND_MODE

Use this to return the rounding mode.

Returns:

  • (BigDecimal::ROUND_MODE) —

    rounding mode



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# File 'lib/money/money.rb', line 256

def self.rounding_mode
  return Thread.current[:money_rounding_mode] if Thread.current[:money_rounding_mode]

  @rounding_mode
end

.rounding_mode=(new_rounding_mode) ⇒ Object 



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# File 'lib/money/money.rb', line 222

def self.rounding_mode=(new_rounding_mode)
  @rounding_mode = new_rounding_mode
end

.setup_defaults ⇒ Object 



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# File 'lib/money/money.rb', line 226

def self.setup_defaults
  # Set the default bank for creating new +Money+ objects.
  self.default_bank = Bank::VariableExchange.instance

  # Default to using currency backend
  self.locale_backend = :currency

  # Default to not using infinite precision cents
  self.default_infinite_precision = false

  # Default rounding mode toward the nearest neighbor; if the neighbors are equidistant, round away from zero
  self.rounding_mode = BigDecimal::ROUND_HALF_UP

  # Default the conversion of Rationals precision to 16
  self.conversion_precision = 16

  # Defaults to the deprecated behavior where
  # `Money.new(0, "USD").eql?(Money.new(0, "EUR"))` is true.
  self.strict_eql_compare = false
end

.with_bank(bank) { ... } ⇒ Object

Thread-safe bank switching method Temporarily changes the default bank in the current thread only

Examples:

Money.with_bank(european_bank) do
  Money.new(100, "USD").exchange_to("EUR")
end

Parameters:

Yields:

  • The block within which the bank will be changed

Returns:

  • (Object) —

    block results



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# File 'lib/money/money.rb', line 209

def self.with_bank(bank)
  original_bank = Thread.current[:money_bank]
  Thread.current[:money_bank] = bank
  yield
ensure
  Thread.current[:money_bank] = original_bank
end

.with_rounding_mode(mode) { ... } ⇒ Object

Temporarily changes the rounding mode in a given block.

Examples:

fee = Money.with_rounding_mode(BigDecimal::ROUND_HALF_DOWN) do
  Money.new(1200) * BigDecimal('0.029')
end

Parameters:

  • mode (BigDecimal::ROUND_MODE)

Yields:

  • The block within which rounding mode will be changed. Its return value will also be the return value of the whole method.

Returns:

  • (Object) —

    block results



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# File 'lib/money/money.rb', line 275

def self.with_rounding_mode(mode)
  original_mode = Thread.current[:money_rounding_mode]
  Thread.current[:money_rounding_mode] = mode
  yield
ensure
  Thread.current[:money_rounding_mode] = original_mode
end

Instance Method Details

#allocate(parts) ⇒ Array<Money> Also known as: split

Splits a given amount in parts without losing pennies. The left-over pennies will be distributed round-robin amongst the parties. This means that parts listed first will likely receive more pennies than ones listed later.

Pass [2, 1, 1] as input to give twice as much to part1 as part2 or part3 which results in 50% of the cash to party1, 25% to part2, and 25% to part3. Passing a number instead of an array will split the amount evenly (without losing pennies when rounding).

Examples:

Money.new(5,   "USD").allocate([3, 7]) #=> [Money.new(2), Money.new(3)]
Money.new(100, "USD").allocate([1, 1, 1]) #=> [Money.new(34), Money.new(33), Money.new(33)]
Money.new(100, "USD").allocate(2) #=> [Money.new(50), Money.new(50)]
Money.new(100, "USD").allocate(3) #=> [Money.new(34), Money.new(33), Money.new(33)]

Parameters:

  • parts (Array<Numeric>, Numeric) —

    how amount should be distributed to parts

Returns:



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# File 'lib/money/money.rb', line 583

def allocate(parts)
  amounts = Money::Allocation.generate(fractional, parts, !Money.default_infinite_precision)
  amounts.map { |amount| dup_with(fractional: amount) }
end

#amount ⇒ BigDecimal

Returns the numerical value of the money.

Examples:

Money.new(1_00, "USD").amount # => BigDecimal("1.00")

Returns:

  • (BigDecimal)

See Also:



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# File 'lib/money/money.rb', line 399

def amount
  to_d
end

#as_ca_dollar ⇒ Money

Receive a money object with the same amount as the current Money object in Canadian dollar.

Examples:

n = Money.new(100, "USD").as_ca_dollar
n.currency #=> #<Money::Currency id: cad>

Returns:



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# File 'lib/money/money.rb', line 549

def as_ca_dollar
  exchange_to("CAD")
end

#as_euro ⇒ Money

Receive a money object with the same amount as the current Money object in euro.

Examples:

n = Money.new(100, "USD").as_euro
n.currency #=> #<Money::Currency id: eur>

Returns:



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# File 'lib/money/money.rb', line 561

def as_euro
  exchange_to("EUR")
end

#as_us_dollar ⇒ Money

Receive a money object with the same amount as the current Money object in United States dollar.

Examples:

n = Money.new(100, "CAD").as_us_dollar
n.currency #=> #<Money::Currency id: usd>

Returns:



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# File 'lib/money/money.rb', line 537

def as_us_dollar
  exchange_to("USD")
end

#cents ⇒ Integer, BigDecimal

Convenience method for fractional part of the amount. Synonym of #fractional

Returns:

  • (Integer) —

    when infinite_precision is false

  • (BigDecimal) —

    when infinite_precision is true

See Also:

  • infinite_precision


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

def cents
  fractional
end

#decimal_mark ⇒ String

Returns a decimal mark according to the locale

Returns:

  • (String) 


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# File 'lib/money/money.rb', line 630

def decimal_mark
  (locale_backend && locale_backend.lookup(:decimal_mark, currency)) ||
    Money::Formatter::DEFAULTS[:decimal_mark]
end

#dollars ⇒ Object

DEPRECATED.

See Also:



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# File 'lib/money/money.rb', line 383

def dollars
  warn "[DEPRECATION] `Money#dollars` is deprecated in favor of " \
       "`Money#amount`."

  amount
end

#dup_with(options = {}) ⇒ Object 



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# File 'lib/money/money.rb', line 635

def dup_with(options = {})
  self.class.new(
    options[:fractional] || fractional,
    options[:currency] || currency,
    bank: options[:bank] || bank
  )
end

#exchange_to(other_currency) {|n| ... } ⇒ Money

Receive the amount of this money object in another Currency.

Examples:

Money.new(2000, "USD").exchange_to("EUR")
Money.new(2000, "USD").exchange_to("EUR") {|x| x.round}
Money.new(2000, "USD").exchange_to(Currency.new("EUR"))

Parameters:

  • other_currency (Currency, String, Symbol) —

    Currency to exchange to.

Yields:

  • (n) —

    Optional block to use when rounding after exchanging one currency for another.

Yield Parameters:

  • n (Float) —

    The resulting float after exchanging one currency for another.

Yield Returns:

  • (Integer)

Returns:



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# File 'lib/money/money.rb', line 520

def exchange_to(other_currency, &rounding_method)
  other_currency = Currency.wrap(other_currency)
  if self.currency == other_currency
    self
  else
    @bank.exchange_with(self, other_currency, &rounding_method)
  end
end

#format(*rules) ⇒ String

Creates a formatted price string according to several rules.

Parameters:

Returns:

  • (String) 


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# File 'lib/money/money.rb', line 613

def format(*rules)
  Money::Formatter.new(self, *rules).to_s
end

#fractional ⇒ Integer, BigDecimal

The value of the monetary amount represented in the fractional or subunit of the currency.

For example, in the US dollar currency the fractional unit is cents, and there are 100 cents in one US dollar. So given the Money representation of one US dollar, the fractional interpretation is 100.

Another example is that of the Kuwaiti dinar. In this case the fractional unit is the fils and there 1000 fils to one Kuwaiti dinar. So given the Money representation of one Kuwaiti dinar, the fractional interpretation is 1000.

Returns:

  • (Integer) —

    when infinite_precision is false

  • (BigDecimal) —

    when infinite_precision is true

See Also:

  • infinite_precision


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

def fractional
  # Ensure we have a BigDecimal. If the Money object is created
  # from YAML, @fractional can end up being set to a Float.
  fractional = as_d(@fractional)

  return_value(fractional)
end

#hash ⇒ Integer

Returns a Integer hash value based on the +fractional+ and +currency+ attributes in order to use functions like & (intersection), group_by, etc.

Examples:

Money.new(100).hash #=> 908351

Returns:

  • (Integer) 


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# File 'lib/money/money.rb', line 410

def hash
  [fractional.hash, currency.hash].hash
end

#inspect ⇒ String

Common inspect function

Returns:

  • (String) 


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# File 'lib/money/money.rb', line 427

def inspect
  "#<#{self.class.name} fractional:#{fractional} currency:#{currency}>"
end

#round(rounding_mode = self.class.rounding_mode, rounding_precision = 0) ⇒ Money

Note:

This method is only useful when operating with infinite_precision turned on. Without infinite_precision values are rounded to the smallest unit of coinage automatically.

Round the monetary amount to smallest unit of coinage.

Examples:

Money.new(10.1, 'USD').round #=> Money.new(10, 'USD')

Returns:

See Also:



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# File 'lib/money/money.rb', line 602

def round(rounding_mode = self.class.rounding_mode, rounding_precision = 0)
  rounded_amount = as_d(@fractional).round(rounding_precision, rounding_mode)
  dup_with(fractional: rounded_amount)
end

#round_to_nearest_cash_value ⇒ Integer, BigDecimal

Round a given amount of money to the nearest possible amount in cash value. For example, in Swiss franc (CHF), the smallest possible amount of cash value is CHF 0.05. Therefore, this method rounds CHF 0.07 to CHF 0.05, and CHF 0.08 to CHF 0.10.

Returns:

  • (Integer) —

    when infinite_precision is false

  • (BigDecimal) —

    when infinite_precision is true

See Also:

  • infinite_precision


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

def round_to_nearest_cash_value
  warn "[DEPRECATION] `round_to_nearest_cash_value` is deprecated - use " \
       "`to_nearest_cash_value.fractional` instead"

  to_nearest_cash_value.fractional
end

#symbol ⇒ String

Uses +Currency#symbol+. If +nil+ is returned, defaults to "¤".

Examples:

Money.new(100, "USD").symbol #=> "$"

Returns:

  • (String) 


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# File 'lib/money/money.rb', line 420

def symbol
  currency.symbol || "¤"
end

#thousands_separator ⇒ String

Returns a thousands separator according to the locale

Returns:

  • (String) 


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# File 'lib/money/money.rb', line 621

def thousands_separator
  (locale_backend && locale_backend.lookup(:thousands_separator, currency)) ||
    Money::Formatter::DEFAULTS[:thousands_separator]
end

#to_d ⇒ BigDecimal

Return the amount of money as a BigDecimal.

Examples:

Money.us_dollar(1_00).to_d #=> BigDecimal("1.00")

Returns:

  • (BigDecimal) 


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# File 'lib/money/money.rb', line 450

def to_d
  as_d(fractional) / as_d(currency.subunit_to_unit)
end

#to_f ⇒ Float

Return the amount of money as a float. Floating points cannot guarantee precision. Therefore, this function should only be used when you no longer need to represent currency or working with another system that requires floats.

Examples:

Money.us_dollar(100).to_f #=> 1.0

Returns:

  • (Float) 


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# File 'lib/money/money.rb', line 473

def to_f
  to_d.to_f
end

#to_i ⇒ Integer

Return the amount of money as a Integer.

Examples:

Money.us_dollar(1_00).to_i #=> 1

Returns:

  • (Integer) 


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# File 'lib/money/money.rb', line 460

def to_i
  to_d.to_i
end

#to_money(given_currency = nil) ⇒ self

Conversion to +self+.

Returns:

  • (self) 


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# File 'lib/money/money.rb', line 495

def to_money(given_currency = nil)
  given_currency = Currency.wrap(given_currency)
  if given_currency.nil? || self.currency == given_currency
    self
  else
    exchange_to(given_currency)
  end
end

#to_nearest_cash_value ⇒ Money

Round a given amount of money to the nearest possible money in cash value. For example, in Swiss franc (CHF), the smallest possible amount of cash value is CHF 0.05. Therefore, this method rounds CHF 0.07 to CHF 0.05, and CHF 0.08 to CHF 0.10.

Returns:



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# File 'lib/money/money.rb', line 84

def to_nearest_cash_value
  unless self.currency.smallest_denomination
    raise UndefinedSmallestDenomination,
          "Smallest denomination of this currency is not defined"
  end

  fractional = as_d(@fractional)
  smallest_denomination = as_d(self.currency.smallest_denomination)
  rounded_value =
    (fractional / smallest_denomination)
      .round(0, self.class.rounding_mode) * smallest_denomination

  dup_with(fractional: return_value(rounded_value))
end

#to_s ⇒ String

Returns the amount of money as a string.

Examples:

Money.ca_dollar(100).to_s #=> "1.00"

Returns:

  • (String) 


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# File 'lib/money/money.rb', line 437

def to_s
  format thousands_separator: '',
         no_cents_if_whole: currency.decimal_places == 0,
         symbol: false,
         ignore_defaults: true
end

#with_currency(new_currency) ⇒ self

Returns a new Money instance in a given currency leaving the amount intact and not performing currency conversion.

Parameters:

  • new_currency (Currency, String, Symbol) —

    Currency of the new object.

Returns:

  • (self) 


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# File 'lib/money/money.rb', line 483

def with_currency(new_currency)
  new_currency = Currency.wrap(new_currency)
  if !new_currency || currency == new_currency
    self
  else
    dup_with(currency: new_currency)
  end
end