An example showing OptionParser backed by Data

options.rb

require 'delegate'
require 'optparse'

class Options < SimpleDelegator
  def initialize(argv = ARGV, &)
    parser = OptionParser.new(&)
    members = members_from parser
    values = values_from parser, argv
    data = data_from members, values

    super(data)
  end

  private

  def members_from(parser)
    parser.top.list.map do |option|
      format option.switch_name
    end
  end

  def values_from(parser, argv)
    into = {}
    parser.parse!(argv, into:)
    into.transform_keys { |key| format key.name }
  end

  def data_from(members, values)
    self.class.const_set(:Into, Data.define(*members))
    Into.new(*values.values_at(*members))
  end

  def format(option) = option.tr('-', '_').to_sym
end

if __FILE__ == $PROGRAM_NAME
  options = Options.new do |parser|
    parser.on '--verbose'
  end

  warn 'verbose' if options.verbose
end