module Sass::Constant

def parse(value, constants, line)
  begin
    operationalize(parenthesize(tokenize(value)), constants).to_s
  rescue Sass::SyntaxError => e
    if e.message == "Constant arithmetic error"
      e.instance_eval do
        @message += ": #{value.dump}."
      end
    end
    e.sass_line = line
    raise e
  end
end