Re: [Boost-users] iterator_adapter conversion to base iterator?

From: David Abrahams (dave_at_[hidden])
Date: 2006-04-07 01:57:12

Sebastian Weber <sebastian.weber_at_[hidden]> writes:

> Hello everybody!
>
> Please don't blame for beeing foolish - I'm using the iterator-adapter
> class for the first time. I converted a standard iterator from a
> std::vector with the iterator_adapter stuff into another class
> random_set_iterator. But at certain points in my programm I need the
> random_set_iterator converted back to the original iterator class from
> the vector class. I noticed the base()-function which basically does the
> job, but I think there should be a more elegant and clearer way to do
> it. Am I wrong or shouldn't an adapted iterator almost always be
> convertible to it's base iterator? 

It shouldn't.  Implicit conversions are generally dangerous; there's
no good reason to allow one here.

> I'm sure, it should not hard to
> implement somthing like this, but how?

You can easily add an 

   operator base_iterator_type() const

to random_set_iterator, but we (the authors of iterator_adaptor) don't
recommend it.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com