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Can anybody offer a specific example of an iterator that has the
capabilities of a forward iterator but no more?

"Dave" <> wrote in message
news:...

> Can anybody offer a specific example of an iterator that has the
> capabilities of a forward iterator but no more?

Look at the sequence class in chapter 15 of "Ruminations on C++."

That class offers behavior similar to Lisp lists, but with the restriction
that all elements of a sequence must have the same type. It also has the
interesting property that the container and iterator classes are the same
type.

In article <>,
"Dave" <> wrote:

> Can anybody offer a specific example of an iterator that has the
> capabilities of a forward iterator but no more?

The iterators of a singly linked list are such an example. You can't
iterate backwards (in constant time).

-Howard

Howard Hinnant <> wrote in news:hinnant-
:

> In article <>,
> "Dave" <> wrote:
>
>> Can anybody offer a specific example of an iterator that has the
>> capabilities of a forward iterator but no more?
>
> The iterators of a singly linked list are such an example. You can't
> iterate backwards (in constant time).
>
> -Howard
>

Or an istream iterator....

In article <Xns96597434BA43Cnntpspamkosturnet@207.35.177.135> ,
Andre Kostur <> wrote:

> Howard Hinnant <> wrote in news:hinnant-
> :
>
> > In article <>,
> > "Dave" <> wrote:
> >
> >> Can anybody offer a specific example of an iterator that has the
> >> capabilities of a forward iterator but no more?
> >
> > The iterators of a singly linked list are such an example. You can't
> > iterate backwards (in constant time).
> >
> > -Howard
> >
>
> Or an istream iterator....

Actually not really, at least if we're using the std::definition of
"forward". A std::istream_iterator fails to meet the forward spec
because it can not be used in multi-pass algorithms. The standard terms
iterators in this class as "input iterators" which have a subset of the
functionality of forward iterators.

-Howard