Hi,

I've found a mismatch:

* bits->list is specified to accept only one argument but sample implementation
  accepts optional argument len

The following is a suggestion:

* It might be useful and consistence if vector->bits also takes
optional argument
  start and end like other vector->* procedures (e.g. vector->string)

Cheers,
--
_/_/
Takashi Kato
E-mail: ktakashi19@gmail.com