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

Eric Niebler writes:

...

The not-so-exciting alternative to having this functionality in xpressive

is

...

going back to C-style matching engines for stream filtering.

Yep. But 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.

Infinite streams (as in presently discussed issue) have an unhealthy tendency to come from the network and end up there as well (and the memory at the filtering node is not that abundant). Files, of course, seldom require such complications.