def rake_check_options(options, *optdecl)
      h = options.dup
      optdecl.each do |name|
        h.delete name
      end
      raise ArgumentError, "no such option: #{h.keys.join(' ')}" unless
        h.empty?
    end
def rake_check_options(options, *optdecl)
      h = options.dup
      optdecl.each do |name|
        h.delete name
      end
      raise ArgumentError, "no such option: #{h.keys.join(' ')}" unless
        h.empty?
    end
Check that the options do not contain options not listed in
 +optdecl+.  An ArgumentError exception is thrown if non-declared
 options are found.