module Forwardable::Extended

def def_hash_delegator(hash, method, key: method, **kwd)
  prefix, suffix, wrap = prepare_delegate(**kwd)
  if suffix
    method = method.to_s.gsub(
      /\?$/, ""
    )
  end
  class_eval delegate_debug(<<-STR), __FILE__, __LINE__ - 9
    def #{method}#{suffix}(*args)
      #{wrap}(
        #{prefix}#{hash}[#{key.inspect}]
      )
    rescue Exception
      if !Forwardable.debug && $@ && $@.respond_to?(:delete_if)
        $@.delete_if do |source|
          source =~ %r"#{Regexp.escape(__FILE__)}"o
        end
      end
      raise
    end
  STR
end