Re: [Boost-users] [xpressive] Using it with input iterators or how far the backtracing will go back

Subject: Re: [Boost-users] [xpressive] Using it with input iterators or how far the backtracing will go back
From: Nat Linden (nat_at_[hidden])
Date: 2010-11-08 09:12:36

On Sun, Nov 7, 2010 at 4:32 PM, Eric Niebler <eric_at_[hidden]> wrote:

On 11/6/2010 4:58 AM, Alex Dubov wrote:
> > Eric Niebler <eric <at> boostpro.com> writes:
> >> On 11/5/2010 10:21 AM, Dominique Devienne wrote:
> >>> On Fri, Nov 5, 2010 at 3:31 AM, Alex Dubov <oakad <at> yahoo.com>
> wrote:
> >>>> So the question is, how can one establish the size for this iterator
> adapter's
> >>>> internal storage so as to avoid match failures due to incomplete
> storage and
> >>>> avoid storing too much unnecessary data?
> >>>
> >>> In the case of single-line matching, backtracking need only going back
> >>> to the start of the current line, so I think the buffering only needs
> >>> to be line based. For arbitrarily long multi-line matching, I don't
> >>> know... --DD
> >>
> >> In that case, the iterator may be backed up all the way to the beginning
> >> of the match, so if the iterator is caching the input, it would need to
> >> cache it all.
>
> like I said, if your stream is like a file stream, then you
> can manipulate the underlying buffers to give you a sliding window,
> paging data in and out as needed.
>

Once upon a time, the Serialization library came with backtracking input
iterators used to parse XML input files with Spirit. I briefly glanced over
more recent Serialization documentation without spotting them. Do they still
exist?