Adding new currency

[kranz]

How can I get EUR as a new unit?

[olbrich]

@kranz have you tried defining a new unit? Something like..

RubyUnits::Unit.define("euro") do |unit|
  unit.scalar = 0.85
  unit.numerator = %w[<dollar>]
  unit.aliases = %w[EUR euro]
  unit.kind = :currency
end

You'd need to keep the conversion updated yourself, and this approach won't parse strings like €100.

Probably you would want to do something like this to the input before trying to create a Unit.

eur = "€100"
eur.gsub(/€\s*(?<euro>#{RubyUnits::Unit::ANY_NUMBER})/) { "#{Regexp.last_match('euro')} EUR" }
#=> "100 EUR"

You may need to tweak that RegExp for your own use case.

You may also want to look into the https://github.com/RubyMoney/money gem as it's purpose built for currency.

Also, if you plan to use RubyUnits for financial math, you may want to consider using BigDecimal instead of Floats for your scalars to avoid issues with rounding.