My take on required keyword arguments in Ruby 2.0. This solution throws a nice backtrace, but still requires a name to be passed in.

required_keyword_arguments.rb

module RequiredKeywordArguments
  def required!(name)
    backtrace = caller_locations(1).map { |c| c.to_s }
    ex = ArgumentError.new("Missing required keyword argument '#{name}'")
    ex.set_backtrace(backtrace)
    raise ex
  end
end

class Foo
  include RequiredKeywordArguments
  
  def bar(baz: required!(:baz))
  
  end
end

Foo.new.bar()

# https://eval.in/127896
# /tmp/execpad-157492e20293/source-157492e20293:13:in `bar': Missing required keyword argument 'baz' (ArgumentError)
#   from /tmp/execpad-157492e20293/source-157492e20293:18:in `<main>'