Currency

Currency is a library useful for dealing with ISO 4217 currency symbols, that respects and enforces correct precision use, and can also perform basic mathematical operations between sets of Currency structs.

Usage

This library is intended to be used with textual representation of a currency. For instance, you create an instance of Currency using an amount, and the currency symbol, i.e., USD for US Dollar. These symbols correspond to ISO 4217.

iex> Currency.new("15.99 USD")
~M"15.99 USD"

To access the ~M sigil, simply import Currency wherever you intend to use it.

This library also supports negative values, rounding extra bits of precision, and simple operations like addition and subtraction. Consider:

iex> import Currency
# Adding two currencies of the same type
iex> ~M"1.99 USD" |> Currency.add(~M"2.29 USD")
~M"4.28 USD"
# Subtracting...
iex> ~M"1.01 CAD" |> Currency.subtract(~M"4.77 CAD")
~M"-3.76 CAD"
# Rounding...
iex> ~M"1.234 USD"
~M"1.23 USD"
iex> ~M"1.236 USD"
~M"1.24 USD"

Installation

This package can be installed by adding currency to your list of dependencies in mix.exs:

def deps do
  [
    {:currency, "~> 1.0.0"}
  ]
end

Documentation can be found at https://hexdocs.pm/currency.